NHS England FHIR Implementation Guide (deprecated)

NHSDigital-Observation

Conformance url	FHIR Module	Maturity Level
https://fhir.nhs.uk/StructureDefinition/NHSDigital-Observation	Diagnostics	trial-use

Combined with
UK Core Observation

Observation	I		Observation	There are no (further) constraints on this element Element Id Observation Short description Measurements and simple assertions Alternate names Vital Signs, Measurement, Results, Tests Definition Measurements and simple assertions made about a patient, device or other subject. Comments Used for simple observations such as device measurements, laboratory atomic results, vital signs, height, weight, smoking status, comments, etc. Other resources are used to provide context for observations such as laboratory reports, etc. Data Type Observation Constraints dom-2:If the resource is contained in another resource, it SHALL NOT contain nested Resources `contained.contained.empty()` dom-4:If a resource is contained in another resource, it SHALL NOT have a meta.versionId or a meta.lastUpdated `contained.meta.versionId.empty() and contained.meta.lastUpdated.empty()` dom-3:If the resource is contained in another resource, it SHALL be referred to from elsewhere in the resource or SHALL refer to the containing resource `contained.where((('#'+id in (%resource.descendants().reference \| %resource.descendants().as(canonical) \| %resource.descendants().as(uri) \| %resource.descendants().as(url))) or descendants().where(reference = '#').exists() or descendants().where(as(canonical) = '#').exists() or descendants().where(as(canonical) = '#').exists()).not()).trace('unmatched', id).empty()` dom-6:A resource should have narrative for robust management text.`div`.exists() dom-5:If a resource is contained in another resource, it SHALL NOT have a security label `contained.meta.security.empty()` obs-7:If Observation.code is the same as an Observation.component.code then the value element associated with the code SHALL NOT be present `value.empty() or component.code.where(coding.intersect(%resource.code.coding).exists()).empty()` obs-6:dataAbsentReason SHALL only be present if Observation.value[x] is not present `dataAbsentReason.empty() or value.empty()` Mappings rim:Entity. Role, or Act workflow:Event sct-concept:< 363787002 \|Observable entity\| v2:OBX rim:Observation[classCode=OBS, moodCode=EVN]
extension	I	0..*	Extension	Element Id Observation.extension Short description Additional content defined by implementations Alternate names extensions, user content Definition May be used to represent additional information that is not part of the basic definition of the resource. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Comments There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Data Type Extension Sliced: Unordered, Open, by url(Value) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ext-1:Must have either extensions or value[x], not both `extension.exists() != value.exists()` Mappings rim:n/a rim:N/A
covid19Testing	S I	0..1	Extension(Complex)	Element Id Observation.extension:covid19Testing Short description Optional Extensions Element Alternate names extensions, user content Definition Optional Extension Element - found in all resources. Comments There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Data Type Extension(Complex) Extension URL https://fhir.nhs.uk/StructureDefinition/Extension-COVID19-TestResult Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ext-1:Must have either extensions or value[x], not both `extension.exists() != value.exists()` Mappings rim:n/a rim:N/A
identifier	S Σ	1..*	Identifier	Element Id Observation.identifier Short description Business Identifier for observation Definition A unique identifier assigned to this observation. For COVID-19 Test History this will be The identifier will be the specimen id. `"identifier": [ { "system": "https://fhir.nhs.uk/Id/SpecimenId", "value": "eb89a392-5b20-11eb-ae93-0242ac130002" } ],` Requirements Allows observations to be distinguished and referenced. Data Type Identifier Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CX / EI (occasionally, more often EI maps to a resource id or a URL) rim:II - The Identifier class is a little looser than the v3 type II because it allows URIs as well as registered OIDs or GUIDs. Also maps to Role[classCode=IDENT] servd:Identifier workflow:Event.identifier w5:FiveWs.identifier v2:OBX.21 For OBX segments from systems without OBX-21 support a combination of ORC/OBR and OBX must be negotiated between trading partners to uniquely identify the OBX segment. Depending on how V2 has been implemented each of these may be an option: 1) OBR-3 + OBX-3 + OBX-4 or 2) OBR-3 + OBR-4 + OBX-3 + OBX-4 or 2) some other way to uniquely ID the OBR/ORC + OBX-3 + OBX-4. rim:id
use	Σ ?!	0..1	codeBinding	There are no (further) constraints on this element Element Id Observation.identifier.use Short description usual \| official \| temp \| secondary \| old (If known) Definition The purpose of this identifier. Requirements Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Comments Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Data Type code Binding Identifies the purpose for this identifier, if known . IdentifierUse (required) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:N/A rim:Role.code or implied by context
type	Σ	0..1	CodeableConceptBinding	There are no (further) constraints on this element Element Id Observation.identifier.type Short description Description of identifier Definition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Requirements Allows users to make use of identifiers when the identifier system is not known. Comments This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. Data Type CodeableConcept Binding A coded type for an identifier that can be used to determine which identifier to use for a specific purpose. Identifier Type Codes (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD v2:CX.5 rim:Role.code or implied by context
system	Σ	1..1	uri	There are no (further) constraints on this element Element Id Observation.identifier.system Short description The namespace for the identifier value Definition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. Requirements There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Comments Identifier.system is always case sensitive. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General http://www.acme.com/identifiers/patient Mappings rim:n/a v2:CX.4 / EI-2-4 rim:II.root or Role.id.root servd:./IdentifierType
value	Σ	1..1	string	There are no (further) constraints on this element Element Id Observation.identifier.value Short description The value that is unique Definition The portion of the identifier typically relevant to the user and which is unique within the context of the system. Comments If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General 123456 Mappings rim:n/a v2:CX.1 / EI.1 rim:II.extension or II.root if system indicates OID or GUID (Or Role.id.extension or root) servd:./Value
period	Σ I	0..1	Period	There are no (further) constraints on this element Element Id Observation.identifier.period Short description Time period when id is/was valid for use Definition Time period during which identifier is/was valid for use. Comments A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. Data Type Period Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` per-1:If present, start SHALL have a lower value than end `start.hasValue().not() or end.hasValue().not() or (start <= end)` Mappings rim:n/a v2:DR rim:IVL<TS>[lowClosed="true" and highClosed="true"] or URG<TS>[lowClosed="true" and highClosed="true"] v2:CX.7 + CX.8 rim:Role.effectiveTime or implied by context servd:./StartDate and ./EndDate
assigner	Σ I	0..1	Reference(UK Core Organization)	There are no (further) constraints on this element Element Id Observation.identifier.assigner Short description Organization that issued id (may be just text) Definition Organization that issued/manages the identifier. Comments The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Data Type Reference(UK Core Organization) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) v2:CX.4 / (CX.4,CX.9,CX.10) rim:II.assigningAuthorityName but note that this is an improper use by the definition of the field. Also Role.scoper servd:./IdentifierIssuingAuthority
basedOn	Σ I	0..*	Reference(DeviceRequest \| ImmunizationRecommendation \| NutritionOrder \| UK Core CarePlan \| UK Core MedicationRequest \| UK Core ServiceRequest)	There are no (further) constraints on this element Element Id Observation.basedOn Short description Fulfills plan, proposal or order Alternate names Fulfills Definition A plan, proposal or order that is fulfilled in whole or in part by this event. For example, a MedicationRequest may require a patient to have laboratory test performed before it is dispensed. Requirements Allows tracing of authorization for the event and tracking whether proposals/recommendations were acted upon. Comments References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. Data Type Reference(DeviceRequest \| ImmunizationRecommendation \| NutritionOrder \| UK Core CarePlan \| UK Core MedicationRequest \| UK Core ServiceRequest) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) workflow:Event.basedOn v2:ORC rim:.inboundRelationship[typeCode=COMP].source[moodCode=EVN]
reference	Σ I	0..1	string	There are no (further) constraints on this element Element Id Observation.basedOn.reference Short description Literal reference, Relative, internal or absolute URL Definition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Comments Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
type	Σ	0..1	uriBinding	There are no (further) constraints on this element Element Id Observation.basedOn.type Short description Type the reference refers to (e.g. "Patient") Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). Comments This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Data Type uri Binding Aa resource (or, for logical models, the URI of the logical model). ResourceType (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
identifier	Σ	0..1	Identifier	There are no (further) constraints on this element Element Id Observation.basedOn.identifier Short description Logical reference, when literal reference is not known Definition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. Comments When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation\|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). Data Type Identifier Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CX / EI (occasionally, more often EI maps to a resource id or a URL) rim:II - The Identifier class is a little looser than the v3 type II because it allows URIs as well as registered OIDs or GUIDs. Also maps to Role[classCode=IDENT] servd:Identifier rim:.identifier
use	Σ ?!	0..1	codeBinding	There are no (further) constraints on this element Element Id Observation.basedOn.identifier.use Short description usual \| official \| temp \| secondary \| old (If known) Definition The purpose of this identifier. Requirements Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Comments Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Data Type code Binding Identifies the purpose for this identifier, if known . IdentifierUse (required) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:N/A rim:Role.code or implied by context
type	Σ	0..1	CodeableConceptBinding	There are no (further) constraints on this element Element Id Observation.basedOn.identifier.type Short description Description of identifier Definition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Requirements Allows users to make use of identifiers when the identifier system is not known. Comments This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. Data Type CodeableConcept Binding A coded type for an identifier that can be used to determine which identifier to use for a specific purpose. Identifier Type Codes (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD v2:CX.5 rim:Role.code or implied by context
system	Σ	0..1	uri	There are no (further) constraints on this element Element Id Observation.basedOn.identifier.system Short description The namespace for the identifier value Definition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. Requirements There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Comments Identifier.system is always case sensitive. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General http://www.acme.com/identifiers/patient Mappings rim:n/a v2:CX.4 / EI-2-4 rim:II.root or Role.id.root servd:./IdentifierType
value	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.basedOn.identifier.value Short description The value that is unique Definition The portion of the identifier typically relevant to the user and which is unique within the context of the system. Comments If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General 123456 Mappings rim:n/a v2:CX.1 / EI.1 rim:II.extension or II.root if system indicates OID or GUID (Or Role.id.extension or root) servd:./Value
period	Σ I	0..1	Period	There are no (further) constraints on this element Element Id Observation.basedOn.identifier.period Short description Time period when id is/was valid for use Definition Time period during which identifier is/was valid for use. Comments A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. Data Type Period Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` per-1:If present, start SHALL have a lower value than end `start.hasValue().not() or end.hasValue().not() or (start <= end)` Mappings rim:n/a v2:DR rim:IVL<TS>[lowClosed="true" and highClosed="true"] or URG<TS>[lowClosed="true" and highClosed="true"] v2:CX.7 + CX.8 rim:Role.effectiveTime or implied by context servd:./StartDate and ./EndDate
assigner	Σ I	0..1	Reference(UK Core Organization)	There are no (further) constraints on this element Element Id Observation.basedOn.identifier.assigner Short description Organization that issued id (may be just text) Definition Organization that issued/manages the identifier. Comments The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Data Type Reference(UK Core Organization) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) v2:CX.4 / (CX.4,CX.9,CX.10) rim:II.assigningAuthorityName but note that this is an improper use by the definition of the field. Also Role.scoper servd:./IdentifierIssuingAuthority
display	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.basedOn.display Short description Text alternative for the resource Definition Plain text narrative that identifies the resource in addition to the resource reference. Comments This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
partOf	Σ I	0..*	Reference(UK Core Imaging Study \| UK Core Immunization \| UK Core MedicationAdministration \| UK Core MedicationDispense \| UK Core MedicationStatement \| UK Core Procedure)	There are no (further) constraints on this element Element Id Observation.partOf Short description Part of referenced event Alternate names Container Definition A larger event of which this particular Observation is a component or step. For example, an observation as part of a procedure. Comments To link an Observation to an Encounter use `encounter`. See the Notes below for guidance on referencing another Observation. Data Type Reference(UK Core Imaging Study \| UK Core Immunization \| UK Core MedicationAdministration \| UK Core MedicationDispense \| UK Core MedicationStatement \| UK Core Procedure) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) workflow:Event.partOf v2:Varies by domain rim:.outboundRelationship[typeCode=FLFS].target
reference	Σ I	0..1	string	There are no (further) constraints on this element Element Id Observation.partOf.reference Short description Literal reference, Relative, internal or absolute URL Definition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Comments Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
type	Σ	0..1	uriBinding	There are no (further) constraints on this element Element Id Observation.partOf.type Short description Type the reference refers to (e.g. "Patient") Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). Comments This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Data Type uri Binding Aa resource (or, for logical models, the URI of the logical model). ResourceType (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
identifier	Σ	0..1	Identifier	There are no (further) constraints on this element Element Id Observation.partOf.identifier Short description Logical reference, when literal reference is not known Definition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. Comments When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation\|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). Data Type Identifier Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CX / EI (occasionally, more often EI maps to a resource id or a URL) rim:II - The Identifier class is a little looser than the v3 type II because it allows URIs as well as registered OIDs or GUIDs. Also maps to Role[classCode=IDENT] servd:Identifier rim:.identifier
use	Σ ?!	0..1	codeBinding	There are no (further) constraints on this element Element Id Observation.partOf.identifier.use Short description usual \| official \| temp \| secondary \| old (If known) Definition The purpose of this identifier. Requirements Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Comments Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Data Type code Binding Identifies the purpose for this identifier, if known . IdentifierUse (required) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:N/A rim:Role.code or implied by context
type	Σ	0..1	CodeableConceptBinding	There are no (further) constraints on this element Element Id Observation.partOf.identifier.type Short description Description of identifier Definition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Requirements Allows users to make use of identifiers when the identifier system is not known. Comments This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. Data Type CodeableConcept Binding A coded type for an identifier that can be used to determine which identifier to use for a specific purpose. Identifier Type Codes (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD v2:CX.5 rim:Role.code or implied by context
system	Σ	0..1	uri	There are no (further) constraints on this element Element Id Observation.partOf.identifier.system Short description The namespace for the identifier value Definition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. Requirements There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Comments Identifier.system is always case sensitive. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General http://www.acme.com/identifiers/patient Mappings rim:n/a v2:CX.4 / EI-2-4 rim:II.root or Role.id.root servd:./IdentifierType
value	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.partOf.identifier.value Short description The value that is unique Definition The portion of the identifier typically relevant to the user and which is unique within the context of the system. Comments If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General 123456 Mappings rim:n/a v2:CX.1 / EI.1 rim:II.extension or II.root if system indicates OID or GUID (Or Role.id.extension or root) servd:./Value
period	Σ I	0..1	Period	There are no (further) constraints on this element Element Id Observation.partOf.identifier.period Short description Time period when id is/was valid for use Definition Time period during which identifier is/was valid for use. Comments A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. Data Type Period Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` per-1:If present, start SHALL have a lower value than end `start.hasValue().not() or end.hasValue().not() or (start <= end)` Mappings rim:n/a v2:DR rim:IVL<TS>[lowClosed="true" and highClosed="true"] or URG<TS>[lowClosed="true" and highClosed="true"] v2:CX.7 + CX.8 rim:Role.effectiveTime or implied by context servd:./StartDate and ./EndDate
assigner	Σ I	0..1	Reference(UK Core Organization)	There are no (further) constraints on this element Element Id Observation.partOf.identifier.assigner Short description Organization that issued id (may be just text) Definition Organization that issued/manages the identifier. Comments The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Data Type Reference(UK Core Organization) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) v2:CX.4 / (CX.4,CX.9,CX.10) rim:II.assigningAuthorityName but note that this is an improper use by the definition of the field. Also Role.scoper servd:./IdentifierIssuingAuthority
display	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.partOf.display Short description Text alternative for the resource Definition Plain text narrative that identifies the resource in addition to the resource reference. Comments This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
status	S Σ ?!	1..1	codeBinding	Element Id Observation.status Short description registered \| preliminary \| final \| amended + Definition The status of the result value. For COVID-19 Test History the status of the observation will always be `final` `"status": "final",` Requirements Need to track the status of individual results. Some results are finalized before the whole report is finalized. Comments This element is labeled as a modifier because the status contains codes that mark the resource as not currently valid. Data Type code Binding Codes providing the status of an observation. ObservationStatus (required) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a workflow:Event.status w5:FiveWs.status sct-concept:< 445584004 \|Report by finality status\| v2:OBX-11 rim:status Amended & Final are differentiated by whether it is the subject of a ControlAct event with a type of "revise"
category	S	0..*	CodeableConceptBinding	Element Id Observation.category Short description Classification of type of observation Definition This is an optional element. If used the category will always be `laboratory` `"category": [ { "coding": [ { "system": "http://terminology.hl7.org/CodeSystem/observation-category", "code": "laboratory", "display": "Laboratory" } ], "text": "Laboratory" } ],` For COVID-19 Tests, the ValueSet SHOULD be used to indicate which test pillar the observation originated. `"category": [ { "coding": [ { "system": "https://fhir.nhs.uk/CodeSystem/covid-test-pillar", "code": "pillar-1", "display": "pillar 1" } ] } ],` Requirements Used for filtering what observations are retrieved and displayed. Comments In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set. Data Type CodeableConcept Sliced: Unordered, Open, by coding.system(Value) Binding Codes for high level observation categories. ObservationCategory (required) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD w5:FiveWs.class rim:.outboundRelationship[typeCode="COMP].target[classCode="LIST", moodCode="EVN"].code
(All Slices)				There are no (further) constraints on this element
coding	Σ	1..*	Coding	There are no (further) constraints on this element Element Id Observation.category.coding Short description Code defined by a terminology system Definition A reference to a code defined by a terminology system. Requirements Allows for alternative encodings within a code system, and translations to other code systems. Comments Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. Data Type Coding Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE subset one of the sets of component 1-3 or 4-6 rim:CV orim:fhir:Coding rdfs:subClassOf dt:CDCoding v2:CE.1-8, CE.10-22 rim:union(., ./translation) orim:fhir:CodeableConcept.coding rdfs:subPropertyOf dt:CD.coding
system	S Σ	1..1	uri	There are no (further) constraints on this element Element Id Observation.category.coding.system Short description Identity of the terminology system Definition The identification of the code system that defines the meaning of the symbol in the code. Requirements Need to be unambiguous about the source of the definition of the symbol. Comments The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.3 rim:./codeSystem orim:*fhir:Coding.system rdfs:subPropertyOf dt:CDCoding.codeSystem
version	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.category.coding.version Short description Version of the system - if relevant Definition The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. Comments Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.7 rim:./codeSystemVersion orim:*fhir:Coding.version rdfs:subPropertyOf dt:CDCoding.codeSystemVersion
code	S Σ	1..1	code	There are no (further) constraints on this element Element Id Observation.category.coding.code Short description Symbol in syntax defined by the system Definition A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). Requirements Need to refer to a particular code in the system. Comments Note that FHIR strings SHALL NOT exceed 1MB in size Data Type code Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.1 rim:./code orim:*fhir:Coding.code rdfs:subPropertyOf dt:CDCoding.code
display	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.category.coding.display Short description Representation defined by the system Definition A representation of the meaning of the code in the system, following the rules of the system. Requirements Need to be able to carry a human-readable meaning of the code for readers that do not know the system. Comments Note that FHIR strings SHALL NOT exceed 1MB in size Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.2 - but note this is not well followed rim:CV.displayName orim:*fhir:Coding.display rdfs:subPropertyOf dt:CDCoding.displayName
userSelected	Σ	0..1	boolean	There are no (further) constraints on this element Element Id Observation.category.coding.userSelected Short description If this coding was chosen directly by the user Definition Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). Requirements This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing. Comments Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. Data Type boolean Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:Sometimes implied by being first rim:CD.codingRationale orim:fhir:Coding.userSelected fhir:mapsTo dt:CDCoding.codingRationale. fhir:Coding.userSelected fhir:hasMap fhir:Coding.userSelected.map. fhir:Coding.userSelected.map a fhir:Map; fhir:target dt:CDCoding.codingRationale. fhir:Coding.userSelected\#true a [ fhir:source "true"; fhir:target dt:CDCoding.codingRationale\#O ]
text	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.category.text Short description Plain text representation of the concept Definition A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. Requirements The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source. Comments Very often the text is the same as a displayName of one of the codings. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.9. But note many systems use CE.2 for this rim:./originalText[mediaType/code="text/plain"]/data orim:fhir:CodeableConcept.text rdfs:subPropertyOf dt:CD.originalText
COVID-TestPillar		0..1	CodeableConceptBinding	Element Id Observation.category:COVID-TestPillar Short description Classification of type of observation Definition A code that classifies the general type of observation being made. Requirements Used for filtering what observations are retrieved and displayed. Comments In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set. Data Type CodeableConcept Binding Codes for high level observation categories. ObservationCategoryCodes (preferred) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD w5:FiveWs.class rim:.outboundRelationship[typeCode="COMP].target[classCode="LIST", moodCode="EVN"].code
coding	Σ	0..*	Coding	There are no (further) constraints on this element Element Id Observation.category:COVID-TestPillar.coding Short description Code defined by a terminology system Definition A reference to a code defined by a terminology system. Requirements Allows for alternative encodings within a code system, and translations to other code systems. Comments Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. Data Type Coding Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE subset one of the sets of component 1-3 or 4-6 rim:CV orim:fhir:Coding rdfs:subClassOf dt:CDCoding v2:CE.1-8, CE.10-22 rim:union(., ./translation) orim:fhir:CodeableConcept.coding rdfs:subPropertyOf dt:CD.coding
system	Σ	0..1	uriFixed Value	Element Id Observation.category:COVID-TestPillar.coding.system Short description Identity of the terminology system Definition The identification of the code system that defines the meaning of the symbol in the code. Requirements Need to be unambiguous about the source of the definition of the symbol. Comments The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Fixed Value https://fhir.nhs.uk/CodeSystem/covid-test-pillar Mappings rim:n/a v2:CE.3 rim:./codeSystem orim:*fhir:Coding.system rdfs:subPropertyOf dt:CDCoding.codeSystem
version	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.category:COVID-TestPillar.coding.version Short description Version of the system - if relevant Definition The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. Comments Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.7 rim:./codeSystemVersion orim:*fhir:Coding.version rdfs:subPropertyOf dt:CDCoding.codeSystemVersion
code	Σ	0..1	code	There are no (further) constraints on this element Element Id Observation.category:COVID-TestPillar.coding.code Short description Symbol in syntax defined by the system Definition A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). Requirements Need to refer to a particular code in the system. Comments Note that FHIR strings SHALL NOT exceed 1MB in size Data Type code Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.1 rim:./code orim:*fhir:Coding.code rdfs:subPropertyOf dt:CDCoding.code
display	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.category:COVID-TestPillar.coding.display Short description Representation defined by the system Definition A representation of the meaning of the code in the system, following the rules of the system. Requirements Need to be able to carry a human-readable meaning of the code for readers that do not know the system. Comments Note that FHIR strings SHALL NOT exceed 1MB in size Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.2 - but note this is not well followed rim:CV.displayName orim:*fhir:Coding.display rdfs:subPropertyOf dt:CDCoding.displayName
userSelected	Σ	0..1	boolean	There are no (further) constraints on this element Element Id Observation.category:COVID-TestPillar.coding.userSelected Short description If this coding was chosen directly by the user Definition Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). Requirements This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing. Comments Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. Data Type boolean Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:Sometimes implied by being first rim:CD.codingRationale orim:fhir:Coding.userSelected fhir:mapsTo dt:CDCoding.codingRationale. fhir:Coding.userSelected fhir:hasMap fhir:Coding.userSelected.map. fhir:Coding.userSelected.map a fhir:Map; fhir:target dt:CDCoding.codingRationale. fhir:Coding.userSelected\#true a [ fhir:source "true"; fhir:target dt:CDCoding.codingRationale\#O ]
text	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.category:COVID-TestPillar.text Short description Plain text representation of the concept Definition A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. Requirements The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source. Comments Very often the text is the same as a displayName of one of the codings. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.9. But note many systems use CE.2 for this rim:./originalText[mediaType/code="text/plain"]/data orim:fhir:CodeableConcept.text rdfs:subPropertyOf dt:CD.originalText
UKCoreCategory		0..*	CodeableConceptBinding	Element Id Observation.category:UKCoreCategory Short description Classification of type of observation Definition A code that classifies the general type of observation being made. Requirements Used for filtering what observations are retrieved and displayed. Comments In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set. Data Type CodeableConcept Binding Codes for high level observation categories. ObservationCategoryCodes (preferred) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD w5:FiveWs.class rim:.outboundRelationship[typeCode="COMP].target[classCode="LIST", moodCode="EVN"].code
coding	Σ	0..*	Coding	There are no (further) constraints on this element Element Id Observation.category:UKCoreCategory.coding Short description Code defined by a terminology system Definition A reference to a code defined by a terminology system. Requirements Allows for alternative encodings within a code system, and translations to other code systems. Comments Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. Data Type Coding Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE subset one of the sets of component 1-3 or 4-6 rim:CV orim:fhir:Coding rdfs:subClassOf dt:CDCoding v2:CE.1-8, CE.10-22 rim:union(., ./translation) orim:fhir:CodeableConcept.coding rdfs:subPropertyOf dt:CD.coding
system	Σ	0..1	uriFixed Value	Element Id Observation.category:UKCoreCategory.coding.system Short description Identity of the terminology system Definition The identification of the code system that defines the meaning of the symbol in the code. Requirements Need to be unambiguous about the source of the definition of the symbol. Comments The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Fixed Value http://terminology.hl7.org/CodeSystem/observation-category Mappings rim:n/a v2:CE.3 rim:./codeSystem orim:*fhir:Coding.system rdfs:subPropertyOf dt:CDCoding.codeSystem
version	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.category:UKCoreCategory.coding.version Short description Version of the system - if relevant Definition The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. Comments Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.7 rim:./codeSystemVersion orim:*fhir:Coding.version rdfs:subPropertyOf dt:CDCoding.codeSystemVersion
code	Σ	0..1	code	There are no (further) constraints on this element Element Id Observation.category:UKCoreCategory.coding.code Short description Symbol in syntax defined by the system Definition A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). Requirements Need to refer to a particular code in the system. Comments Note that FHIR strings SHALL NOT exceed 1MB in size Data Type code Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.1 rim:./code orim:*fhir:Coding.code rdfs:subPropertyOf dt:CDCoding.code
display	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.category:UKCoreCategory.coding.display Short description Representation defined by the system Definition A representation of the meaning of the code in the system, following the rules of the system. Requirements Need to be able to carry a human-readable meaning of the code for readers that do not know the system. Comments Note that FHIR strings SHALL NOT exceed 1MB in size Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.2 - but note this is not well followed rim:CV.displayName orim:*fhir:Coding.display rdfs:subPropertyOf dt:CDCoding.displayName
userSelected	Σ	0..1	boolean	There are no (further) constraints on this element Element Id Observation.category:UKCoreCategory.coding.userSelected Short description If this coding was chosen directly by the user Definition Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). Requirements This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing. Comments Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. Data Type boolean Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:Sometimes implied by being first rim:CD.codingRationale orim:fhir:Coding.userSelected fhir:mapsTo dt:CDCoding.codingRationale. fhir:Coding.userSelected fhir:hasMap fhir:Coding.userSelected.map. fhir:Coding.userSelected.map a fhir:Map; fhir:target dt:CDCoding.codingRationale. fhir:Coding.userSelected\#true a [ fhir:source "true"; fhir:target dt:CDCoding.codingRationale\#O ]
text	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.category:UKCoreCategory.text Short description Plain text representation of the concept Definition A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. Requirements The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source. Comments Very often the text is the same as a displayName of one of the codings. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.9. But note many systems use CE.2 for this rim:./originalText[mediaType/code="text/plain"]/data orim:fhir:CodeableConcept.text rdfs:subPropertyOf dt:CD.originalText
code	S Σ	1..1	CodeableConcept	Element Id Observation.code Short description Type of observation (code / type) Alternate names Name Definition Type of observation, for COVID-10 see Observation Definition for `code` values. `"code": { "coding": [ { "system": "http://snomed.info/sct", "code": "871555000", "display": "Detection of ribonucleic acid of Severe acute respiratory syndrome coronavirus 2" } ] },` Requirements Knowing what kind of observation is being made is essential to understanding the observation. Comments All code-value and, if present, component.code-component.value pairs need to be taken into account to correctly understand the meaning of the observation. Data Type CodeableConcept Binding Codes identifying names of simple observations. LOINCCodes (example) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD workflow:Event.code w5:FiveWs.what[x] sct-concept:< 363787002 \|Observable entity\| OR < 386053000 \|Evaluation procedure\| v2:OBX-3 rim:code sct-attr:116680003 \|Is a\|
coding	Σ	0..*	Coding	There are no (further) constraints on this element Element Id Observation.code.coding Short description Code defined by a terminology system Definition A reference to a code defined by a terminology system. Requirements Allows for alternative encodings within a code system, and translations to other code systems. Comments Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. Data Type Coding Sliced: Unordered, Open, by system(Value) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE subset one of the sets of component 1-3 or 4-6 rim:CV orim:fhir:Coding rdfs:subClassOf dt:CDCoding v2:CE.1-8, CE.10-22 rim:union(., ./translation) orim:fhir:CodeableConcept.coding rdfs:subPropertyOf dt:CD.coding
snomedCT	Σ	0..*	CodingBinding	There are no (further) constraints on this element Element Id Observation.code.coding:snomedCT Short description Code defined by a terminology system Definition A reference to a code defined by a terminology system. Requirements Allows for alternative encodings within a code system, and translations to other code systems. Comments Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. Data Type Coding Binding A code from the SNOMED Clinical Terminology UK coding system describing a type of observation UKCoreObservationType (preferred) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE subset one of the sets of component 1-3 or 4-6 rim:CV orim:fhir:Coding rdfs:subClassOf dt:CDCoding v2:CE.1-8, CE.10-22 rim:union(., ./translation) orim:fhir:CodeableConcept.coding rdfs:subPropertyOf dt:CD.coding
system	Σ	1..1	uriFixed Value	There are no (further) constraints on this element Element Id Observation.code.coding:snomedCT.system Short description Identity of the terminology system Definition The identification of the code system that defines the meaning of the symbol in the code. Requirements Need to be unambiguous about the source of the definition of the symbol. Comments The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Fixed Value http://snomed.info/sct Mappings rim:n/a v2:CE.3 rim:./codeSystem orim:*fhir:Coding.system rdfs:subPropertyOf dt:CDCoding.codeSystem
version	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.code.coding:snomedCT.version Short description Version of the system - if relevant Definition The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. Comments Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.7 rim:./codeSystemVersion orim:*fhir:Coding.version rdfs:subPropertyOf dt:CDCoding.codeSystemVersion
code	Σ	1..1	code	There are no (further) constraints on this element Element Id Observation.code.coding:snomedCT.code Short description Symbol in syntax defined by the system Definition A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). Requirements Need to refer to a particular code in the system. Comments Note that FHIR strings SHALL NOT exceed 1MB in size Data Type code Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.1 rim:./code orim:*fhir:Coding.code rdfs:subPropertyOf dt:CDCoding.code
display	Σ	1..1	string	There are no (further) constraints on this element Element Id Observation.code.coding:snomedCT.display Short description Representation defined by the system Definition A representation of the meaning of the code in the system, following the rules of the system. Requirements Need to be able to carry a human-readable meaning of the code for readers that do not know the system. Comments Note that FHIR strings SHALL NOT exceed 1MB in size Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.2 - but note this is not well followed rim:CV.displayName orim:*fhir:Coding.display rdfs:subPropertyOf dt:CDCoding.displayName
userSelected	Σ	0..1	boolean	There are no (further) constraints on this element Element Id Observation.code.coding:snomedCT.userSelected Short description If this coding was chosen directly by the user Definition Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). Requirements This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing. Comments Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. Data Type boolean Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:Sometimes implied by being first rim:CD.codingRationale orim:fhir:Coding.userSelected fhir:mapsTo dt:CDCoding.codingRationale. fhir:Coding.userSelected fhir:hasMap fhir:Coding.userSelected.map. fhir:Coding.userSelected.map a fhir:Map; fhir:target dt:CDCoding.codingRationale. fhir:Coding.userSelected\#true a [ fhir:source "true"; fhir:target dt:CDCoding.codingRationale\#O ]
loinc	Σ	0..*	Coding	There are no (further) constraints on this element Element Id Observation.code.coding:loinc Short description Code defined by a terminology system Definition A reference to a code defined by a terminology system. Requirements Allows for alternative encodings within a code system, and translations to other code systems. Comments Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. Data Type Coding Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE subset one of the sets of component 1-3 or 4-6 rim:CV orim:fhir:Coding rdfs:subClassOf dt:CDCoding v2:CE.1-8, CE.10-22 rim:union(., ./translation) orim:fhir:CodeableConcept.coding rdfs:subPropertyOf dt:CD.coding
system	Σ	1..1	uriFixed Value	There are no (further) constraints on this element Element Id Observation.code.coding:loinc.system Short description Identity of the terminology system Definition The identification of the code system that defines the meaning of the symbol in the code. Requirements Need to be unambiguous about the source of the definition of the symbol. Comments The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Fixed Value http://loinc.org Mappings rim:n/a v2:CE.3 rim:./codeSystem orim:*fhir:Coding.system rdfs:subPropertyOf dt:CDCoding.codeSystem
version	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.code.coding:loinc.version Short description Version of the system - if relevant Definition The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. Comments Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.7 rim:./codeSystemVersion orim:*fhir:Coding.version rdfs:subPropertyOf dt:CDCoding.codeSystemVersion
code	Σ	1..1	code	There are no (further) constraints on this element Element Id Observation.code.coding:loinc.code Short description Symbol in syntax defined by the system Definition A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). Requirements Need to refer to a particular code in the system. Comments Note that FHIR strings SHALL NOT exceed 1MB in size Data Type code Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.1 rim:./code orim:*fhir:Coding.code rdfs:subPropertyOf dt:CDCoding.code
display	Σ	1..1	string	There are no (further) constraints on this element Element Id Observation.code.coding:loinc.display Short description Representation defined by the system Definition A representation of the meaning of the code in the system, following the rules of the system. Requirements Need to be able to carry a human-readable meaning of the code for readers that do not know the system. Comments Note that FHIR strings SHALL NOT exceed 1MB in size Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.2 - but note this is not well followed rim:CV.displayName orim:*fhir:Coding.display rdfs:subPropertyOf dt:CDCoding.displayName
userSelected	Σ	0..1	boolean	There are no (further) constraints on this element Element Id Observation.code.coding:loinc.userSelected Short description If this coding was chosen directly by the user Definition Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). Requirements This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing. Comments Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. Data Type boolean Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:Sometimes implied by being first rim:CD.codingRationale orim:fhir:Coding.userSelected fhir:mapsTo dt:CDCoding.codingRationale. fhir:Coding.userSelected fhir:hasMap fhir:Coding.userSelected.map. fhir:Coding.userSelected.map a fhir:Map; fhir:target dt:CDCoding.codingRationale. fhir:Coding.userSelected\#true a [ fhir:source "true"; fhir:target dt:CDCoding.codingRationale\#O ]
text	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.code.text Short description Plain text representation of the concept Definition A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. Requirements The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source. Comments Very often the text is the same as a displayName of one of the codings. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.9. But note many systems use CE.2 for this rim:./originalText[mediaType/code="text/plain"]/data orim:fhir:CodeableConcept.text rdfs:subPropertyOf dt:CD.originalText
subject	S Σ I	1..1	Reference(Group \| UK Core Device \| UK Core Location \| NHSDigitalPatientMinimal)	Element Id Observation.subject Short description Who and/or what the observation is about Definition The NHS Number will be an identifier reference which can be used with PDS FHIR API to return Patient demographics. If a local Patient is available, a reference to this will be present (e.g. "Patient/123") `"subject": { "reference": "Patient/123", "identifier": [ { "system": "https://fhir.nhs.uk/Id/nhs-number", "value": "987123456" } ] },` Requirements Observations have no value if you don't know who or what they're about. Comments One would expect this element to be a cardinality of 1..1. The only circumstance in which the subject can be missing is when the observation is made by a device that does not know the patient. In this case, the observation SHALL be matched to a patient through some context/channel matching technique, and at this point, the observation should be updated. Data Type Reference(Group \| UK Core Device \| UK Core Location \| NHSDigitalPatientMinimal) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` patient-reference:subject - An identifier reference or resource reference must be provided `(reference.exists() or (identifier.exists()))` patient-nhs:Supplied NHS Number is outside the English and Welsh NHS Number range or length of the number is wrong. `identifier.where(system='https://fhir.nhs.uk/Id/nhs-number').exists().not() or (identifier.where(system='https://fhir.nhs.uk/Id/nhs-number').exists() and identifier.where(system='https://fhir.nhs.uk/Id/nhs-number').value.matches('^([456789]{1}[0-9]{9})$'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) workflow:Event.subject w5:FiveWs.subject[x] v2:PID-3 rim:participation[typeCode=RTGT] w5:FiveWs.subject
reference	Σ I	0..1	string	There are no (further) constraints on this element Element Id Observation.subject.reference Short description Literal reference, Relative, internal or absolute URL Definition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Comments Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
type	Σ	0..1	uriBinding	There are no (further) constraints on this element Element Id Observation.subject.type Short description Type the reference refers to (e.g. "Patient") Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). Comments This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Data Type uri Binding Aa resource (or, for logical models, the URI of the logical model). ResourceType (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
identifier	Σ	0..1	Identifier	There are no (further) constraints on this element Element Id Observation.subject.identifier Short description Logical reference, when literal reference is not known Definition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. Comments When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation\|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). Data Type Identifier Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CX / EI (occasionally, more often EI maps to a resource id or a URL) rim:II - The Identifier class is a little looser than the v3 type II because it allows URIs as well as registered OIDs or GUIDs. Also maps to Role[classCode=IDENT] servd:Identifier rim:.identifier
use	Σ ?!	0..1	codeBinding	There are no (further) constraints on this element Element Id Observation.subject.identifier.use Short description usual \| official \| temp \| secondary \| old (If known) Definition The purpose of this identifier. Requirements Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Comments Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Data Type code Binding Identifies the purpose for this identifier, if known . IdentifierUse (required) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:N/A rim:Role.code or implied by context
type	Σ	0..1	CodeableConceptBinding	There are no (further) constraints on this element Element Id Observation.subject.identifier.type Short description Description of identifier Definition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Requirements Allows users to make use of identifiers when the identifier system is not known. Comments This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. Data Type CodeableConcept Binding A coded type for an identifier that can be used to determine which identifier to use for a specific purpose. Identifier Type Codes (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD v2:CX.5 rim:Role.code or implied by context
system	Σ	1..1	uriFixed Value	Element Id Observation.subject.identifier.system Short description The namespace for the identifier value Definition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. Requirements There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Comments Identifier.system is always case sensitive. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Fixed Value https://fhir.nhs.uk/Id/nhs-number Mappings rim:n/a v2:CX.4 / EI-2-4 rim:II.root or Role.id.root servd:./IdentifierType
value	Σ	1..1	string	There are no (further) constraints on this element Element Id Observation.subject.identifier.value Short description The value that is unique Definition The portion of the identifier typically relevant to the user and which is unique within the context of the system. Comments If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General 123456 Mappings rim:n/a v2:CX.1 / EI.1 rim:II.extension or II.root if system indicates OID or GUID (Or Role.id.extension or root) servd:./Value
period	Σ I	0..1	Period	There are no (further) constraints on this element Element Id Observation.subject.identifier.period Short description Time period when id is/was valid for use Definition Time period during which identifier is/was valid for use. Comments A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. Data Type Period Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` per-1:If present, start SHALL have a lower value than end `start.hasValue().not() or end.hasValue().not() or (start <= end)` Mappings rim:n/a v2:DR rim:IVL<TS>[lowClosed="true" and highClosed="true"] or URG<TS>[lowClosed="true" and highClosed="true"] v2:CX.7 + CX.8 rim:Role.effectiveTime or implied by context servd:./StartDate and ./EndDate
assigner	Σ I	0..1	Reference(UK Core Organization)	There are no (further) constraints on this element Element Id Observation.subject.identifier.assigner Short description Organization that issued id (may be just text) Definition Organization that issued/manages the identifier. Comments The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Data Type Reference(UK Core Organization) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) v2:CX.4 / (CX.4,CX.9,CX.10) rim:II.assigningAuthorityName but note that this is an improper use by the definition of the field. Also Role.scoper servd:./IdentifierIssuingAuthority
display	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.subject.display Short description Text alternative for the resource Definition Plain text narrative that identifies the resource in addition to the resource reference. Comments This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
focus	Σ I	0..*	Reference(Resource)	There are no (further) constraints on this element Element Id Observation.focus Short description What the observation is about, when it is not about the subject of record Definition The actual focus of an observation when it is not the patient of record representing something or someone associated with the patient such as a spouse, parent, fetus, or donor. For example, fetus observations in a mother's record. The focus of an observation could also be an existing condition, an intervention, the subject's diet, another observation of the subject, or a body structure such as tumor or implanted device. An example use case would be using the Observation resource to capture whether the mother is trained to change her child's tracheostomy tube. In this example, the child is the patient of record and the mother is the focus. Comments Typically, an observation is made about the subject - a patient, or group of patients, location, or device - and the distinction between the subject and what is directly measured for an observation is specified in the observation code itself ( e.g., "Blood Glucose") and does not need to be represented separately using this element. Use `specimen` if a reference to a specimen is required. If a code is required instead of a resource use either `bodysite` for bodysites or the standard extension focusCode. Data Type Reference(Resource) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) w5:FiveWs.subject[x] v2:OBX-3 rim:participation[typeCode=SBJ] w5:FiveWs.subject
reference	Σ I	0..1	string	There are no (further) constraints on this element Element Id Observation.focus.reference Short description Literal reference, Relative, internal or absolute URL Definition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Comments Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
type	Σ	0..1	uriBinding	There are no (further) constraints on this element Element Id Observation.focus.type Short description Type the reference refers to (e.g. "Patient") Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). Comments This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Data Type uri Binding Aa resource (or, for logical models, the URI of the logical model). ResourceType (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
identifier	Σ	0..1	Identifier	There are no (further) constraints on this element Element Id Observation.focus.identifier Short description Logical reference, when literal reference is not known Definition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. Comments When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation\|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). Data Type Identifier Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CX / EI (occasionally, more often EI maps to a resource id or a URL) rim:II - The Identifier class is a little looser than the v3 type II because it allows URIs as well as registered OIDs or GUIDs. Also maps to Role[classCode=IDENT] servd:Identifier rim:.identifier
use	Σ ?!	0..1	codeBinding	There are no (further) constraints on this element Element Id Observation.focus.identifier.use Short description usual \| official \| temp \| secondary \| old (If known) Definition The purpose of this identifier. Requirements Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Comments Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Data Type code Binding Identifies the purpose for this identifier, if known . IdentifierUse (required) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:N/A rim:Role.code or implied by context
type	Σ	0..1	CodeableConceptBinding	There are no (further) constraints on this element Element Id Observation.focus.identifier.type Short description Description of identifier Definition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Requirements Allows users to make use of identifiers when the identifier system is not known. Comments This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. Data Type CodeableConcept Binding A coded type for an identifier that can be used to determine which identifier to use for a specific purpose. Identifier Type Codes (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD v2:CX.5 rim:Role.code or implied by context
system	Σ	0..1	uri	There are no (further) constraints on this element Element Id Observation.focus.identifier.system Short description The namespace for the identifier value Definition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. Requirements There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Comments Identifier.system is always case sensitive. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General http://www.acme.com/identifiers/patient Mappings rim:n/a v2:CX.4 / EI-2-4 rim:II.root or Role.id.root servd:./IdentifierType
value	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.focus.identifier.value Short description The value that is unique Definition The portion of the identifier typically relevant to the user and which is unique within the context of the system. Comments If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General 123456 Mappings rim:n/a v2:CX.1 / EI.1 rim:II.extension or II.root if system indicates OID or GUID (Or Role.id.extension or root) servd:./Value
period	Σ I	0..1	Period	There are no (further) constraints on this element Element Id Observation.focus.identifier.period Short description Time period when id is/was valid for use Definition Time period during which identifier is/was valid for use. Comments A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. Data Type Period Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` per-1:If present, start SHALL have a lower value than end `start.hasValue().not() or end.hasValue().not() or (start <= end)` Mappings rim:n/a v2:DR rim:IVL<TS>[lowClosed="true" and highClosed="true"] or URG<TS>[lowClosed="true" and highClosed="true"] v2:CX.7 + CX.8 rim:Role.effectiveTime or implied by context servd:./StartDate and ./EndDate
assigner	Σ I	0..1	Reference(UK Core Organization)	There are no (further) constraints on this element Element Id Observation.focus.identifier.assigner Short description Organization that issued id (may be just text) Definition Organization that issued/manages the identifier. Comments The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Data Type Reference(UK Core Organization) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) v2:CX.4 / (CX.4,CX.9,CX.10) rim:II.assigningAuthorityName but note that this is an improper use by the definition of the field. Also Role.scoper servd:./IdentifierIssuingAuthority
display	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.focus.display Short description Text alternative for the resource Definition Plain text narrative that identifies the resource in addition to the resource reference. Comments This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
encounter	Σ I	0..1	Reference(UK Core Encounter)	There are no (further) constraints on this element Element Id Observation.encounter Short description Healthcare event during which this observation is made Alternate names Context Definition The healthcare event (e.g. a patient and healthcare provider interaction) during which this observation is made. Requirements For some observations it may be important to know the link between an observation and a particular encounter. Comments This will typically be the encounter the event occurred within, but some events may be initiated prior to or after the official completion of an encounter but still be tied to the context of the encounter (e.g. pre-admission laboratory tests). Data Type Reference(UK Core Encounter) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) workflow:Event.context w5:FiveWs.context v2:PV1 rim:inboundRelationship[typeCode=COMP].source[classCode=ENC, moodCode=EVN]
reference	Σ I	0..1	string	There are no (further) constraints on this element Element Id Observation.encounter.reference Short description Literal reference, Relative, internal or absolute URL Definition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Comments Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
type	Σ	0..1	uriBinding	There are no (further) constraints on this element Element Id Observation.encounter.type Short description Type the reference refers to (e.g. "Patient") Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). Comments This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Data Type uri Binding Aa resource (or, for logical models, the URI of the logical model). ResourceType (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
identifier	Σ	0..1	Identifier	There are no (further) constraints on this element Element Id Observation.encounter.identifier Short description Logical reference, when literal reference is not known Definition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. Comments When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation\|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). Data Type Identifier Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CX / EI (occasionally, more often EI maps to a resource id or a URL) rim:II - The Identifier class is a little looser than the v3 type II because it allows URIs as well as registered OIDs or GUIDs. Also maps to Role[classCode=IDENT] servd:Identifier rim:.identifier
use	Σ ?!	0..1	codeBinding	There are no (further) constraints on this element Element Id Observation.encounter.identifier.use Short description usual \| official \| temp \| secondary \| old (If known) Definition The purpose of this identifier. Requirements Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Comments Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Data Type code Binding Identifies the purpose for this identifier, if known . IdentifierUse (required) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:N/A rim:Role.code or implied by context
type	Σ	0..1	CodeableConceptBinding	There are no (further) constraints on this element Element Id Observation.encounter.identifier.type Short description Description of identifier Definition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Requirements Allows users to make use of identifiers when the identifier system is not known. Comments This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. Data Type CodeableConcept Binding A coded type for an identifier that can be used to determine which identifier to use for a specific purpose. Identifier Type Codes (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD v2:CX.5 rim:Role.code or implied by context
system	Σ	0..1	uri	There are no (further) constraints on this element Element Id Observation.encounter.identifier.system Short description The namespace for the identifier value Definition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. Requirements There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Comments Identifier.system is always case sensitive. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General http://www.acme.com/identifiers/patient Mappings rim:n/a v2:CX.4 / EI-2-4 rim:II.root or Role.id.root servd:./IdentifierType
value	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.encounter.identifier.value Short description The value that is unique Definition The portion of the identifier typically relevant to the user and which is unique within the context of the system. Comments If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General 123456 Mappings rim:n/a v2:CX.1 / EI.1 rim:II.extension or II.root if system indicates OID or GUID (Or Role.id.extension or root) servd:./Value
period	Σ I	0..1	Period	There are no (further) constraints on this element Element Id Observation.encounter.identifier.period Short description Time period when id is/was valid for use Definition Time period during which identifier is/was valid for use. Comments A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. Data Type Period Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` per-1:If present, start SHALL have a lower value than end `start.hasValue().not() or end.hasValue().not() or (start <= end)` Mappings rim:n/a v2:DR rim:IVL<TS>[lowClosed="true" and highClosed="true"] or URG<TS>[lowClosed="true" and highClosed="true"] v2:CX.7 + CX.8 rim:Role.effectiveTime or implied by context servd:./StartDate and ./EndDate
assigner	Σ I	0..1	Reference(UK Core Organization)	There are no (further) constraints on this element Element Id Observation.encounter.identifier.assigner Short description Organization that issued id (may be just text) Definition Organization that issued/manages the identifier. Comments The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Data Type Reference(UK Core Organization) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) v2:CX.4 / (CX.4,CX.9,CX.10) rim:II.assigningAuthorityName but note that this is an improper use by the definition of the field. Also Role.scoper servd:./IdentifierIssuingAuthority
display	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.encounter.display Short description Text alternative for the resource Definition Plain text narrative that identifies the resource in addition to the resource reference. Comments This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
effective[x]	S Σ	1..1		Element Id Observation.effective[x] Short description Clinically relevant time/time-period for observation Alternate names Occurrence Definition The date and time the result was asserted. `"effectiveDateTime": "2020-09-23T13:00:08.476+00:00"` Requirements Knowing when an observation was deemed true is important to its relevance as well as determining trends. Comments At least a date should be present unless this observation is a historical report. For recording imprecise or "fuzzy" times (For example, a blood glucose measurement taken "after breakfast") use the Timing datatype which allow the measurement to be tied to regular life events. Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a workflow:Event.occurrence[x] w5:FiveWs.done[x] v2:OBX-14, and/or OBX-19 after v2.4 (depends on who observation made) rim:effectiveTime
effectiveDateTime			dateTime	Data Type dateTime
issued	Σ	0..1	instant	There are no (further) constraints on this element Element Id Observation.issued Short description Date/Time this version was made available Definition The date and time this version of the observation was made available to providers, typically after the results have been reviewed and verified. Comments For Observations that don’t require review and verification, it may be the same as the `lastUpdated` time of the resource itself. For Observations that do require review and verification for certain updates, it might not be the same as the `lastUpdated` time of the resource itself due to a non-clinically significant update that doesn’t require the new version to be reviewed and verified again. Data Type instant Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a w5:FiveWs.recorded v2:OBR.22 (or MSH.7), or perhaps OBX-19 (depends on who observation made) rim:participation[typeCode=AUT].time
performer	S Σ I	0..*	NHSDigitalReference(NHSDigitalOrganization \| UK Core CareTeam \| NHSDigitalPatient \| NHSDigitalPractitionerRoleMinimal)	Element Id Observation.performer Short description A reference from one resource to another Definition Who was responsible for asserting the observed value as "true". `"performer": [ { "type": "Organization", "identifier": { "type": { "coding": [ { "system": "https://fhir.nhs.uk/CodeSystem/organisation-role", "code": "173", "display": "PATHOLOGY LAB" } ] }, "value": "LFD004" } }, { "type": "Organization", "identifier": { "type": { "coding": [ { "system": "https://fhir.nhs.uk/Id/OrgType", "code": "TestCentreId", "display": "Testing Centre" } ] }, "value": "WKE03" } } ]` Requirements May give a degree of confidence in the observation and also indicates where follow-up questions should be directed. Comments References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. Data Type NHSDigitalReference(NHSDigitalOrganization \| UK Core CareTeam \| NHSDigitalPatient \| NHSDigitalPractitionerRoleMinimal) Allowed aggregation: referenced Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` performer:An identifier reference or resource reference must be provided `(reference.exists() or identifier.exists())` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) workflow:Event.performer.actor w5:FiveWs.actor v2:OBX.15 / (Practitioner) OBX-16, PRT-5:PRT-4='RO' / (Device) OBX-18 , PRT-10:PRT-4='EQUIP' / (Organization) OBX-23, PRT-8:PRT-4='PO' rim:participation[typeCode=PRF]
reference	Σ I	0..1	string	There are no (further) constraints on this element Element Id Observation.performer.reference Short description Literal reference, Relative, internal or absolute URL Definition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Comments Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
type	Σ	0..1	uriBinding	There are no (further) constraints on this element Element Id Observation.performer.type Short description Type the reference refers to (e.g. "Patient") Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). Comments This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Data Type uri Binding Aa resource (or, for logical models, the URI of the logical model). ResourceType (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
identifier	Σ	0..1	Identifier	There are no (further) constraints on this element Element Id Observation.performer.identifier Short description Logical reference, when literal reference is not known Definition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. Comments When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation\|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). Data Type Identifier Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CX / EI (occasionally, more often EI maps to a resource id or a URL) rim:II - The Identifier class is a little looser than the v3 type II because it allows URIs as well as registered OIDs or GUIDs. Also maps to Role[classCode=IDENT] servd:Identifier rim:.identifier
use	Σ ?!	0..1	codeBinding	There are no (further) constraints on this element Element Id Observation.performer.identifier.use Short description usual \| official \| temp \| secondary \| old (If known) Definition The purpose of this identifier. Requirements Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Comments Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Data Type code Binding Identifies the purpose for this identifier, if known . IdentifierUse (required) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:N/A rim:Role.code or implied by context
type	Σ	0..1	CodeableConceptBinding	There are no (further) constraints on this element Element Id Observation.performer.identifier.type Short description Description of identifier Definition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Requirements Allows users to make use of identifiers when the identifier system is not known. Comments This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. Data Type CodeableConcept Binding A coded type for an identifier that can be used to determine which identifier to use for a specific purpose. Identifier Type Codes (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD v2:CX.5 rim:Role.code or implied by context
system	Σ	0..1	uri	There are no (further) constraints on this element Element Id Observation.performer.identifier.system Short description The namespace for the identifier value Definition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. Requirements There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Comments Identifier.system is always case sensitive. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General http://www.acme.com/identifiers/patient Mappings rim:n/a v2:CX.4 / EI-2-4 rim:II.root or Role.id.root servd:./IdentifierType
value	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.performer.identifier.value Short description The value that is unique Definition The portion of the identifier typically relevant to the user and which is unique within the context of the system. Comments If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General 123456 Mappings rim:n/a v2:CX.1 / EI.1 rim:II.extension or II.root if system indicates OID or GUID (Or Role.id.extension or root) servd:./Value
period	Σ I	0..1	Period	There are no (further) constraints on this element Element Id Observation.performer.identifier.period Short description Time period when id is/was valid for use Definition Time period during which identifier is/was valid for use. Comments A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. Data Type Period Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` per-1:If present, start SHALL have a lower value than end `start.hasValue().not() or end.hasValue().not() or (start <= end)` Mappings rim:n/a v2:DR rim:IVL<TS>[lowClosed="true" and highClosed="true"] or URG<TS>[lowClosed="true" and highClosed="true"] v2:CX.7 + CX.8 rim:Role.effectiveTime or implied by context servd:./StartDate and ./EndDate
assigner	Σ I	0..1	Reference(UK Core Organization)	There are no (further) constraints on this element Element Id Observation.performer.identifier.assigner Short description Organization that issued id (may be just text) Definition Organization that issued/manages the identifier. Comments The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Data Type Reference(UK Core Organization) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) v2:CX.4 / (CX.4,CX.9,CX.10) rim:II.assigningAuthorityName but note that this is an improper use by the definition of the field. Also Role.scoper servd:./IdentifierIssuingAuthority
display	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.performer.display Short description Text alternative for the resource Definition Plain text narrative that identifies the resource in addition to the resource reference. Comments This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
value[x]	S Σ I	0..1		Element Id Observation.value[x] Short description Actual result Definition COVID-19 valueCodeableConcept The COVID 19 test result. This is a SNOMED CT from the valueSet associated with the `code`, see Observation Definition `"valueCodeableConcept": { "coding": [ { "system": "http://snomed.info/sct", "code": "1240581000000104", "display": "SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) detection result positive" } ], "text": "SARS-CoV-2-ORGY" },` Requirements An observation exists to have a value, though it might not if it is in error, or if it represents a group of observations. Comments An observation may have; 1) a single value here, 2) both a value and a set of related or component values, or 3) only a set of related or component values. If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the Notes section below. Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a sct-concept:< 441742003 \|Evaluation finding\| v2:OBX.2, OBX.5, OBX.6 rim:value sct-attr:363714003 \|Interprets\|
valueQuantity			Quantity	There are no (further) constraints on this element Data Type Quantity
valueCodeableConcept			CodeableConcept	There are no (further) constraints on this element Data Type CodeableConcept
valueString			string	There are no (further) constraints on this element Data Type string
valueBoolean			boolean	There are no (further) constraints on this element Data Type boolean
valueInteger			integer	There are no (further) constraints on this element Data Type integer
valueRange			Range	There are no (further) constraints on this element Data Type Range
valueRatio			Ratio	There are no (further) constraints on this element Data Type Ratio
valueSampledData			SampledData	There are no (further) constraints on this element Data Type SampledData
valueTime			time	There are no (further) constraints on this element Data Type time
valueDateTime			dateTime	There are no (further) constraints on this element Data Type dateTime
valuePeriod			Period	There are no (further) constraints on this element Data Type Period
dataAbsentReason	I	0..1	CodeableConceptBinding	There are no (further) constraints on this element Element Id Observation.dataAbsentReason Short description Why the result is missing Definition Provides a reason why the expected value in the element Observation.value[x] is missing. Requirements For many results it is necessary to handle exceptional values in measurements. Comments Null or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "specimen unsatisfactory". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Note that an observation may only be reported if there are values to report. For example differential cell counts values may be reported only when > 0. Because of these options, use-case agreements are required to interpret general observations for null or exceptional values. Data Type CodeableConcept Binding Codes specifying why the result (`Observation.value[x]`) is missing. DataAbsentReason (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD v2:N/A rim:value.nullFlavor
interpretation		0..*	CodeableConceptBinding	There are no (further) constraints on this element Element Id Observation.interpretation Short description High, low, normal, etc. Alternate names Abnormal Flag Definition A categorical assessment of an observation value. For example, high, low, normal. Requirements For some results, particularly numeric results, an interpretation is necessary to fully understand the significance of a result. Comments Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. Data Type CodeableConcept Binding Codes identifying interpretations of observations. ObservationInterpretationCodes (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD sct-concept:< 260245000 \|Findings values\| v2:OBX-8 rim:interpretationCode sct-attr:363713009 \|Has interpretation\|
note		0..*	Annotation	There are no (further) constraints on this element Element Id Observation.note Short description Comments about the observation Definition Comments about the observation or the results. Requirements Need to be able to provide free text additional information. Comments May include general statements about the observation, or statements about significant, unexpected or unreliable results values, or information about its source when relevant to its interpretation. Data Type Annotation Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:N/A rim:Act v2:NTE.3 (partner NTE to OBX, or sometimes another (child?) OBX) rim:subjectOf.observationEvent[code="annotation"].value
author[x]	Σ	0..1		There are no (further) constraints on this element Element Id Observation.note.author[x] Short description Individual responsible for the annotation Definition The individual responsible for making the annotation. Comments Organization is used when there's no need for specific attribution as to who made the comment. Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:N/A rim:Act.participant[typeCode=AUT].role
authorString			string	There are no (further) constraints on this element Data Type string
authorReference			Reference(UK Core Organization \| UK Core Patient \| UK Core Practitioner \| UK Core RelatedPerson)	There are no (further) constraints on this element Data Type Reference(UK Core Organization \| UK Core Patient \| UK Core Practitioner \| UK Core RelatedPerson)
time	Σ	0..1	dateTime	There are no (further) constraints on this element Element Id Observation.note.time Short description When the annotation was made Definition Indicates when this particular annotation was made. Data Type dateTime Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:N/A rim:Act.effectiveTime
text	Σ	1..1	markdown	There are no (further) constraints on this element Element Id Observation.note.text Short description The annotation - text content (as markdown) Definition The text of the annotation in markdown format. Comments Systems are not required to have markdown support, so the text should be readable without markdown processing. The markdown syntax is GFM - see https://github.github.com/gfm/ Data Type markdown Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:N/A rim:Act.text
bodySite		0..1	CodeableConcept	There are no (further) constraints on this element Element Id Observation.bodySite Short description Observed body part Definition Indicates the site on the subject's body where the observation was made (i.e. the target site). Comments Only used if not implicit in code found in Observation.code. In many systems, this may be represented as a related observation instead of an inline component. If the use case requires BodySite to be handled as a separate resource (e.g. to identify and track separately) then use the standard extension bodySite. Data Type CodeableConcept Binding Codes describing anatomical locations. May include laterality. SNOMEDCTBodyStructures (example) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD sct-concept:< 123037004 \|Body structure\| v2:OBX-20 rim:targetSiteCode sct-attr:718497002 \|Inherent location\|
coding	Σ	0..*	Coding	There are no (further) constraints on this element Element Id Observation.bodySite.coding Short description Code defined by a terminology system Definition A reference to a code defined by a terminology system. Requirements Allows for alternative encodings within a code system, and translations to other code systems. Comments Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. Data Type Coding Sliced: Unordered, Open, by code(Value), system(Value) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE subset one of the sets of component 1-3 or 4-6 rim:CV orim:fhir:Coding rdfs:subClassOf dt:CDCoding v2:CE.1-8, CE.10-22 rim:union(., ./translation) orim:fhir:CodeableConcept.coding rdfs:subPropertyOf dt:CD.coding
snomedCT	Σ	0..1	CodingBinding	There are no (further) constraints on this element Element Id Observation.bodySite.coding:snomedCT Short description Code defined by a terminology system Definition A reference to a code defined by a terminology system. Requirements Allows for alternative encodings within a code system, and translations to other code systems. Comments Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. Data Type Coding Binding A code from the SNOMED Clinical Terminology UK with the expression (<<442083009 \|anatomical or acquired body structure\|) UKCoreBodySite (preferred) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE subset one of the sets of component 1-3 or 4-6 rim:CV orim:fhir:Coding rdfs:subClassOf dt:CDCoding v2:CE.1-8, CE.10-22 rim:union(., ./translation) orim:fhir:CodeableConcept.coding rdfs:subPropertyOf dt:CD.coding
system	Σ	1..1	uriFixed Value	There are no (further) constraints on this element Element Id Observation.bodySite.coding:snomedCT.system Short description Identity of the terminology system Definition The identification of the code system that defines the meaning of the symbol in the code. Requirements Need to be unambiguous about the source of the definition of the symbol. Comments The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Fixed Value http://snomed.info/sct Mappings rim:n/a v2:CE.3 rim:./codeSystem orim:*fhir:Coding.system rdfs:subPropertyOf dt:CDCoding.codeSystem
version	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.bodySite.coding:snomedCT.version Short description Version of the system - if relevant Definition The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. Comments Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.7 rim:./codeSystemVersion orim:*fhir:Coding.version rdfs:subPropertyOf dt:CDCoding.codeSystemVersion
code	Σ	1..1	code	There are no (further) constraints on this element Element Id Observation.bodySite.coding:snomedCT.code Short description Symbol in syntax defined by the system Definition A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). Requirements Need to refer to a particular code in the system. Comments Note that FHIR strings SHALL NOT exceed 1MB in size Data Type code Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.1 rim:./code orim:*fhir:Coding.code rdfs:subPropertyOf dt:CDCoding.code
display	Σ	1..1	string	There are no (further) constraints on this element Element Id Observation.bodySite.coding:snomedCT.display Short description Representation defined by the system Definition A representation of the meaning of the code in the system, following the rules of the system. Requirements Need to be able to carry a human-readable meaning of the code for readers that do not know the system. Comments Note that FHIR strings SHALL NOT exceed 1MB in size Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.2 - but note this is not well followed rim:CV.displayName orim:*fhir:Coding.display rdfs:subPropertyOf dt:CDCoding.displayName
userSelected	Σ	0..1	boolean	There are no (further) constraints on this element Element Id Observation.bodySite.coding:snomedCT.userSelected Short description If this coding was chosen directly by the user Definition Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). Requirements This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing. Comments Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. Data Type boolean Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:Sometimes implied by being first rim:CD.codingRationale orim:fhir:Coding.userSelected fhir:mapsTo dt:CDCoding.codingRationale. fhir:Coding.userSelected fhir:hasMap fhir:Coding.userSelected.map. fhir:Coding.userSelected.map a fhir:Map; fhir:target dt:CDCoding.codingRationale. fhir:Coding.userSelected\#true a [ fhir:source "true"; fhir:target dt:CDCoding.codingRationale\#O ]
text	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.bodySite.text Short description Plain text representation of the concept Definition A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. Requirements The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source. Comments Very often the text is the same as a displayName of one of the codings. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.9. But note many systems use CE.2 for this rim:./originalText[mediaType/code="text/plain"]/data orim:fhir:CodeableConcept.text rdfs:subPropertyOf dt:CD.originalText
method	S	0..1	CodeableConceptBinding	Element Id Observation.method Short description How it was done Definition The name of the test that was performed, this is a SNOMED CT concept. `"method": { "coding": [ { "system": "http://snomed.info/sct", "code": "1240461000000109", "display": "Measurement of SARS-CoV-2 antibody (procedure)" } ] },` Requirements In some cases, method can impact results and is thus used for determining whether results can be compared or determining significance of results. Comments Only used if not implicit in code for Observation.code. Data Type CodeableConcept Binding Methods for simple observations. ObservationMethods (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD v2:OBX-17 rim:methodCode
coding	Σ	0..*	Coding	There are no (further) constraints on this element Element Id Observation.method.coding Short description Code defined by a terminology system Definition A reference to a code defined by a terminology system. Requirements Allows for alternative encodings within a code system, and translations to other code systems. Comments Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. Data Type Coding Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE subset one of the sets of component 1-3 or 4-6 rim:CV orim:fhir:Coding rdfs:subClassOf dt:CDCoding v2:CE.1-8, CE.10-22 rim:union(., ./translation) orim:fhir:CodeableConcept.coding rdfs:subPropertyOf dt:CD.coding
system	Σ	1..1	uri	There are no (further) constraints on this element Element Id Observation.method.coding.system Short description Identity of the terminology system Definition The identification of the code system that defines the meaning of the symbol in the code. Requirements Need to be unambiguous about the source of the definition of the symbol. Comments The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.3 rim:./codeSystem orim:*fhir:Coding.system rdfs:subPropertyOf dt:CDCoding.codeSystem
version	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.method.coding.version Short description Version of the system - if relevant Definition The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. Comments Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.7 rim:./codeSystemVersion orim:*fhir:Coding.version rdfs:subPropertyOf dt:CDCoding.codeSystemVersion
code	Σ	1..1	code	There are no (further) constraints on this element Element Id Observation.method.coding.code Short description Symbol in syntax defined by the system Definition A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). Requirements Need to refer to a particular code in the system. Comments Note that FHIR strings SHALL NOT exceed 1MB in size Data Type code Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.1 rim:./code orim:*fhir:Coding.code rdfs:subPropertyOf dt:CDCoding.code
display	Σ	1..1	string	There are no (further) constraints on this element Element Id Observation.method.coding.display Short description Representation defined by the system Definition A representation of the meaning of the code in the system, following the rules of the system. Requirements Need to be able to carry a human-readable meaning of the code for readers that do not know the system. Comments Note that FHIR strings SHALL NOT exceed 1MB in size Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.2 - but note this is not well followed rim:CV.displayName orim:*fhir:Coding.display rdfs:subPropertyOf dt:CDCoding.displayName
userSelected	Σ	0..1	boolean	There are no (further) constraints on this element Element Id Observation.method.coding.userSelected Short description If this coding was chosen directly by the user Definition Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). Requirements This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing. Comments Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. Data Type boolean Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:Sometimes implied by being first rim:CD.codingRationale orim:fhir:Coding.userSelected fhir:mapsTo dt:CDCoding.codingRationale. fhir:Coding.userSelected fhir:hasMap fhir:Coding.userSelected.map. fhir:Coding.userSelected.map a fhir:Map; fhir:target dt:CDCoding.codingRationale. fhir:Coding.userSelected\#true a [ fhir:source "true"; fhir:target dt:CDCoding.codingRationale\#O ]
text	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.method.text Short description Plain text representation of the concept Definition A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. Requirements The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source. Comments Very often the text is the same as a displayName of one of the codings. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.9. But note many systems use CE.2 for this rim:./originalText[mediaType/code="text/plain"]/data orim:fhir:CodeableConcept.text rdfs:subPropertyOf dt:CD.originalText
specimen	S I	0..1	Reference(UK Core Specimen)	Element Id Observation.specimen Short description Specimen used for this observation Definition For COVID-19 Test History. The identifier of the specimen used for the test. `"specimen": { "identifier": { "system": "https://fhir.nhs.uk/Id/SpecimenId", "value": "eb89a392-5b20-11eb-ae93-0242ac130002" } },` Comments Should only be used if not implicit in code found in `Observation.code`. Observations are not made on specimens themselves; they are made on a subject, but in many cases by the means of a specimen. Note that although specimens are often involved, they are not always tracked and reported explicitly. Also note that observation resources may be used in contexts that track the specimen explicitly (e.g. Diagnostic Report). Data Type Reference(UK Core Specimen) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) sct-concept:< 123038009 \|Specimen\| v2:SPM segment rim:participation[typeCode=SPC].specimen sct-attr:704319004 \|Inherent in\|
reference	Σ I	0..1	string	There are no (further) constraints on this element Element Id Observation.specimen.reference Short description Literal reference, Relative, internal or absolute URL Definition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Comments Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
type	Σ	0..1	uriBinding	There are no (further) constraints on this element Element Id Observation.specimen.type Short description Type the reference refers to (e.g. "Patient") Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). Comments This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Data Type uri Binding Aa resource (or, for logical models, the URI of the logical model). ResourceType (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
identifier	Σ	0..1	Identifier	There are no (further) constraints on this element Element Id Observation.specimen.identifier Short description Logical reference, when literal reference is not known Definition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. Comments When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation\|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). Data Type Identifier Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CX / EI (occasionally, more often EI maps to a resource id or a URL) rim:II - The Identifier class is a little looser than the v3 type II because it allows URIs as well as registered OIDs or GUIDs. Also maps to Role[classCode=IDENT] servd:Identifier rim:.identifier
use	Σ ?!	0..1	codeBinding	There are no (further) constraints on this element Element Id Observation.specimen.identifier.use Short description usual \| official \| temp \| secondary \| old (If known) Definition The purpose of this identifier. Requirements Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Comments Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Data Type code Binding Identifies the purpose for this identifier, if known . IdentifierUse (required) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:N/A rim:Role.code or implied by context
type	Σ	0..1	CodeableConceptBinding	There are no (further) constraints on this element Element Id Observation.specimen.identifier.type Short description Description of identifier Definition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Requirements Allows users to make use of identifiers when the identifier system is not known. Comments This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. Data Type CodeableConcept Binding A coded type for an identifier that can be used to determine which identifier to use for a specific purpose. Identifier Type Codes (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD v2:CX.5 rim:Role.code or implied by context
system	Σ	1..1	uri	There are no (further) constraints on this element Element Id Observation.specimen.identifier.system Short description The namespace for the identifier value Definition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. Requirements There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Comments Identifier.system is always case sensitive. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General http://www.acme.com/identifiers/patient Mappings rim:n/a v2:CX.4 / EI-2-4 rim:II.root or Role.id.root servd:./IdentifierType
value	Σ	1..1	string	There are no (further) constraints on this element Element Id Observation.specimen.identifier.value Short description The value that is unique Definition The portion of the identifier typically relevant to the user and which is unique within the context of the system. Comments If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General 123456 Mappings rim:n/a v2:CX.1 / EI.1 rim:II.extension or II.root if system indicates OID or GUID (Or Role.id.extension or root) servd:./Value
period	Σ I	0..1	Period	There are no (further) constraints on this element Element Id Observation.specimen.identifier.period Short description Time period when id is/was valid for use Definition Time period during which identifier is/was valid for use. Comments A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. Data Type Period Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` per-1:If present, start SHALL have a lower value than end `start.hasValue().not() or end.hasValue().not() or (start <= end)` Mappings rim:n/a v2:DR rim:IVL<TS>[lowClosed="true" and highClosed="true"] or URG<TS>[lowClosed="true" and highClosed="true"] v2:CX.7 + CX.8 rim:Role.effectiveTime or implied by context servd:./StartDate and ./EndDate
assigner	Σ I	0..1	Reference(UK Core Organization)	There are no (further) constraints on this element Element Id Observation.specimen.identifier.assigner Short description Organization that issued id (may be just text) Definition Organization that issued/manages the identifier. Comments The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Data Type Reference(UK Core Organization) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) v2:CX.4 / (CX.4,CX.9,CX.10) rim:II.assigningAuthorityName but note that this is an improper use by the definition of the field. Also Role.scoper servd:./IdentifierIssuingAuthority
display	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.specimen.display Short description Text alternative for the resource Definition Plain text narrative that identifies the resource in addition to the resource reference. Comments This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
device	S I	0..1	Reference(DeviceMetric \| UK Core Device)	Element Id Observation.device Short description (Measurement) Device Definition Details of the COVID-19 test kit used. `"device": { "identifier": { "system": "https://fhir.nhs.uk/Id/Covid19-TestKit", "value": "LFT" }, "display": "Lateral Flow Test" }` Comments Note that this is not meant to represent a device involved in the transmission of the result, e.g., a gateway. Such devices may be documented using the Provenance resource where relevant. Data Type Reference(DeviceMetric \| UK Core Device) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) sct-concept:< 49062001 \|Device\| v2:OBX-17 / PRT -10 rim:participation[typeCode=DEV] sct-attr:424226004 \|Using device\|
reference	Σ I	0..1	string	There are no (further) constraints on this element Element Id Observation.device.reference Short description Literal reference, Relative, internal or absolute URL Definition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Comments Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
type	Σ	0..1	uriBinding	There are no (further) constraints on this element Element Id Observation.device.type Short description Type the reference refers to (e.g. "Patient") Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). Comments This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Data Type uri Binding Aa resource (or, for logical models, the URI of the logical model). ResourceType (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
identifier	Σ	0..1	Identifier	There are no (further) constraints on this element Element Id Observation.device.identifier Short description Logical reference, when literal reference is not known Definition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. Comments When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation\|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). Data Type Identifier Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CX / EI (occasionally, more often EI maps to a resource id or a URL) rim:II - The Identifier class is a little looser than the v3 type II because it allows URIs as well as registered OIDs or GUIDs. Also maps to Role[classCode=IDENT] servd:Identifier rim:.identifier
use	Σ ?!	0..1	codeBinding	There are no (further) constraints on this element Element Id Observation.device.identifier.use Short description usual \| official \| temp \| secondary \| old (If known) Definition The purpose of this identifier. Requirements Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Comments Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Data Type code Binding Identifies the purpose for this identifier, if known . IdentifierUse (required) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:N/A rim:Role.code or implied by context
type	Σ	0..1	CodeableConceptBinding	There are no (further) constraints on this element Element Id Observation.device.identifier.type Short description Description of identifier Definition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Requirements Allows users to make use of identifiers when the identifier system is not known. Comments This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. Data Type CodeableConcept Binding A coded type for an identifier that can be used to determine which identifier to use for a specific purpose. Identifier Type Codes (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD v2:CX.5 rim:Role.code or implied by context
system	Σ	1..1	uri	There are no (further) constraints on this element Element Id Observation.device.identifier.system Short description The namespace for the identifier value Definition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. Requirements There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Comments Identifier.system is always case sensitive. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General http://www.acme.com/identifiers/patient Mappings rim:n/a v2:CX.4 / EI-2-4 rim:II.root or Role.id.root servd:./IdentifierType
value	Σ	1..1	string	There are no (further) constraints on this element Element Id Observation.device.identifier.value Short description The value that is unique Definition The portion of the identifier typically relevant to the user and which is unique within the context of the system. Comments If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General 123456 Mappings rim:n/a v2:CX.1 / EI.1 rim:II.extension or II.root if system indicates OID or GUID (Or Role.id.extension or root) servd:./Value
period	Σ I	0..1	Period	There are no (further) constraints on this element Element Id Observation.device.identifier.period Short description Time period when id is/was valid for use Definition Time period during which identifier is/was valid for use. Comments A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. Data Type Period Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` per-1:If present, start SHALL have a lower value than end `start.hasValue().not() or end.hasValue().not() or (start <= end)` Mappings rim:n/a v2:DR rim:IVL<TS>[lowClosed="true" and highClosed="true"] or URG<TS>[lowClosed="true" and highClosed="true"] v2:CX.7 + CX.8 rim:Role.effectiveTime or implied by context servd:./StartDate and ./EndDate
assigner	Σ I	0..1	Reference(UK Core Organization)	There are no (further) constraints on this element Element Id Observation.device.identifier.assigner Short description Organization that issued id (may be just text) Definition Organization that issued/manages the identifier. Comments The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Data Type Reference(UK Core Organization) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) v2:CX.4 / (CX.4,CX.9,CX.10) rim:II.assigningAuthorityName but note that this is an improper use by the definition of the field. Also Role.scoper servd:./IdentifierIssuingAuthority
display	Σ	1..1	string	There are no (further) constraints on this element Element Id Observation.device.display Short description Text alternative for the resource Definition Plain text narrative that identifies the resource in addition to the resource reference. Comments This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
referenceRange	I	0..*	BackboneElement	There are no (further) constraints on this element Element Id Observation.referenceRange Short description Provides guide for interpretation Definition Guidance on how to interpret the value by comparison to a normal or recommended range. Multiple reference ranges are interpreted as an "OR". In other words, to represent two distinct target populations, two `referenceRange` elements would be used. Requirements Knowing what values are considered "normal" can help evaluate the significance of a particular result. Need to be able to provide multiple reference ranges for different contexts. Comments Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. Data Type BackboneElement Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` obs-3:Must have at least a low or a high or text `low.exists() or high.exists() or text.exists()` Mappings rim:n/a v2:OBX.7 rim:outboundRelationship[typeCode=REFV]/target[classCode=OBS, moodCode=EVN]
low	I	0..1	SimpleQuantity	There are no (further) constraints on this element Element Id Observation.referenceRange.low Short description Low Range, if relevant Definition The value of the low bound of the reference range. The low bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the low bound is omitted, it is assumed to be meaningless (e.g. reference range is <=2.3). Comments The context of use may frequently define what kind of quantity this is and therefore what kind of units can be used. The context of use may also restrict the values for the comparator. Data Type SimpleQuantity Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` qty-3:If a code for the unit is present, the system SHALL also be present `code.empty() or system.exists()` sqty-1:The comparator is not used on a SimpleQuantity `comparator.empty()` Mappings rim:n/a v2:SN (see also Range) or CQ rim:PQ, IVL<PQ>, MO, CO, depending on the values v2:OBX-7 rim:value:IVL_PQ.low
high	I	0..1	SimpleQuantity	There are no (further) constraints on this element Element Id Observation.referenceRange.high Short description High Range, if relevant Definition The value of the high bound of the reference range. The high bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the high bound is omitted, it is assumed to be meaningless (e.g. reference range is >= 2.3). Comments The context of use may frequently define what kind of quantity this is and therefore what kind of units can be used. The context of use may also restrict the values for the comparator. Data Type SimpleQuantity Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` qty-3:If a code for the unit is present, the system SHALL also be present `code.empty() or system.exists()` sqty-1:The comparator is not used on a SimpleQuantity `comparator.empty()` Mappings rim:n/a v2:SN (see also Range) or CQ rim:PQ, IVL<PQ>, MO, CO, depending on the values v2:OBX-7 rim:value:IVL_PQ.high
type		0..1	CodeableConceptBinding	There are no (further) constraints on this element Element Id Observation.referenceRange.type Short description Reference range qualifier Definition Codes to indicate the what part of the targeted reference population it applies to. For example, the normal or therapeutic range. Requirements Need to be able to say what kind of reference range this is - normal, recommended, therapeutic, etc., - for proper interpretation. Comments This SHOULD be populated if there is more than one range. If this element is not present then the normal range is assumed. Data Type CodeableConcept Binding Code for the meaning of a reference range. ObservationReferenceRangeMeaningCodes (preferred) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD sct-concept:< 260245000 \|Findings values\| OR < 365860008 \|General clinical state finding\| OR < 250171008 \|Clinical history or observation findings\| OR < 415229000 \|Racial group\| OR < 365400002 \|Finding of puberty stage\| OR < 443938003 \|Procedure carried out on subject\| v2:OBX-10 rim:interpretationCode
appliesTo		0..*	CodeableConcept	There are no (further) constraints on this element Element Id Observation.referenceRange.appliesTo Short description Reference range population Definition Codes to indicate the target population this reference range applies to. For example, a reference range may be based on the normal population or a particular sex or race. Multiple `appliesTo` are interpreted as an "AND" of the target populations. For example, to represent a target population of African American females, both a code of female and a code for African American would be used. Requirements Need to be able to identify the target population for proper interpretation. Comments This SHOULD be populated if there is more than one range. If this element is not present then the normal population is assumed. Data Type CodeableConcept Binding Codes identifying the population the reference range applies to. ObservationReferenceRangeAppliesToCodes (example) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD sct-concept:< 260245000 \|Findings values\| OR < 365860008 \|General clinical state finding\| OR < 250171008 \|Clinical history or observation findings\| OR < 415229000 \|Racial group\| OR < 365400002 \|Finding of puberty stage\| OR < 443938003 \|Procedure carried out on subject\| v2:OBX-10 rim:interpretationCode
age	I	0..1	Range	There are no (further) constraints on this element Element Id Observation.referenceRange.age Short description Applicable age range, if relevant Definition The age at which this reference range is applicable. This is a neonatal age (e.g. number of weeks at term) if the meaning says so. Requirements Some analytes vary greatly over age. Comments The stated low and high value are assumed to have arbitrarily high precision when it comes to determining which values are in the range. I.e. 1.99 is not in the range 2 -> 3. Data Type Range Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` rng-2:If present, low SHALL have a lower value than high `low.empty() or high.empty() or (low <= high)` Mappings rim:n/a v2:NR and also possibly SN (but see also quantity) rim:IVL<QTY[not(type="TS")]> [lowClosed="true" and highClosed="true"]or URG<QTY[not(type="TS")]> rim:outboundRelationship[typeCode=PRCN].targetObservationCriterion[code="age"].value
text		0..1	string	There are no (further) constraints on this element Element Id Observation.referenceRange.text Short description Text based reference range in an observation Definition Text based reference range in an observation which may be used when a quantitative range is not appropriate for an observation. An example would be a reference value of "Negative" or a list or table of "normals". Comments Note that FHIR strings SHALL NOT exceed 1MB in size Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:OBX-7 rim:value:ST
hasMember	Σ I	0..*	Reference(MolecularSequence \| UK Core Observation \| UK Core QuestionnaireResponse)	There are no (further) constraints on this element Element Id Observation.hasMember Short description Related resource that belongs to the Observation group Definition This observation is a group observation (e.g. a battery, a panel of tests, a set of vital sign measurements) that includes the target as a member of the group. Comments When using this element, an observation will typically have either a value or a set of related resources, although both may be present in some cases. For a discussion on the ways Observations can assembled in groups together, see Notes below. Note that a system may calculate results from QuestionnaireResponse into a final score and represent the score as an Observation. Data Type Reference(MolecularSequence \| UK Core Observation \| UK Core QuestionnaireResponse) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) v2:Relationships established by OBX-4 usage rim:outBoundRelationship
reference	Σ I	0..1	string	There are no (further) constraints on this element Element Id Observation.hasMember.reference Short description Literal reference, Relative, internal or absolute URL Definition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Comments Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
type	Σ	0..1	uriBinding	There are no (further) constraints on this element Element Id Observation.hasMember.type Short description Type the reference refers to (e.g. "Patient") Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). Comments This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Data Type uri Binding Aa resource (or, for logical models, the URI of the logical model). ResourceType (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
identifier	Σ	0..1	Identifier	There are no (further) constraints on this element Element Id Observation.hasMember.identifier Short description Logical reference, when literal reference is not known Definition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. Comments When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation\|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). Data Type Identifier Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CX / EI (occasionally, more often EI maps to a resource id or a URL) rim:II - The Identifier class is a little looser than the v3 type II because it allows URIs as well as registered OIDs or GUIDs. Also maps to Role[classCode=IDENT] servd:Identifier rim:.identifier
use	Σ ?!	0..1	codeBinding	There are no (further) constraints on this element Element Id Observation.hasMember.identifier.use Short description usual \| official \| temp \| secondary \| old (If known) Definition The purpose of this identifier. Requirements Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Comments Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Data Type code Binding Identifies the purpose for this identifier, if known . IdentifierUse (required) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:N/A rim:Role.code or implied by context
type	Σ	0..1	CodeableConceptBinding	There are no (further) constraints on this element Element Id Observation.hasMember.identifier.type Short description Description of identifier Definition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Requirements Allows users to make use of identifiers when the identifier system is not known. Comments This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. Data Type CodeableConcept Binding A coded type for an identifier that can be used to determine which identifier to use for a specific purpose. Identifier Type Codes (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD v2:CX.5 rim:Role.code or implied by context
system	Σ	0..1	uri	There are no (further) constraints on this element Element Id Observation.hasMember.identifier.system Short description The namespace for the identifier value Definition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. Requirements There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Comments Identifier.system is always case sensitive. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General http://www.acme.com/identifiers/patient Mappings rim:n/a v2:CX.4 / EI-2-4 rim:II.root or Role.id.root servd:./IdentifierType
value	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.hasMember.identifier.value Short description The value that is unique Definition The portion of the identifier typically relevant to the user and which is unique within the context of the system. Comments If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General 123456 Mappings rim:n/a v2:CX.1 / EI.1 rim:II.extension or II.root if system indicates OID or GUID (Or Role.id.extension or root) servd:./Value
period	Σ I	0..1	Period	There are no (further) constraints on this element Element Id Observation.hasMember.identifier.period Short description Time period when id is/was valid for use Definition Time period during which identifier is/was valid for use. Comments A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. Data Type Period Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` per-1:If present, start SHALL have a lower value than end `start.hasValue().not() or end.hasValue().not() or (start <= end)` Mappings rim:n/a v2:DR rim:IVL<TS>[lowClosed="true" and highClosed="true"] or URG<TS>[lowClosed="true" and highClosed="true"] v2:CX.7 + CX.8 rim:Role.effectiveTime or implied by context servd:./StartDate and ./EndDate
assigner	Σ I	0..1	Reference(UK Core Organization)	There are no (further) constraints on this element Element Id Observation.hasMember.identifier.assigner Short description Organization that issued id (may be just text) Definition Organization that issued/manages the identifier. Comments The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Data Type Reference(UK Core Organization) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) v2:CX.4 / (CX.4,CX.9,CX.10) rim:II.assigningAuthorityName but note that this is an improper use by the definition of the field. Also Role.scoper servd:./IdentifierIssuingAuthority
display	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.hasMember.display Short description Text alternative for the resource Definition Plain text narrative that identifies the resource in addition to the resource reference. Comments This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
derivedFrom	Σ I	0..*	Reference(Media \| MolecularSequence \| UK Core DocumentReference \| UK Core Imaging Study \| UK Core Observation \| UK Core QuestionnaireResponse)	There are no (further) constraints on this element Element Id Observation.derivedFrom Short description Related measurements the observation is made from Definition The target resource that represents a measurement from which this observation value is derived. For example, a calculated anion gap or a fetal measurement based on an ultrasound image. Comments All the reference choices that are listed in this element can represent clinical observations and other measurements that may be the source for a derived value. The most common reference will be another Observation. For a discussion on the ways Observations can assembled in groups together, see Notes below. Data Type Reference(Media \| MolecularSequence \| UK Core DocumentReference \| UK Core Imaging Study \| UK Core Observation \| UK Core QuestionnaireResponse) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) v2:Relationships established by OBX-4 usage rim:.targetObservation
reference	Σ I	0..1	string	There are no (further) constraints on this element Element Id Observation.derivedFrom.reference Short description Literal reference, Relative, internal or absolute URL Definition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Comments Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
type	Σ	0..1	uriBinding	There are no (further) constraints on this element Element Id Observation.derivedFrom.type Short description Type the reference refers to (e.g. "Patient") Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). Comments This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Data Type uri Binding Aa resource (or, for logical models, the URI of the logical model). ResourceType (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
identifier	Σ	0..1	Identifier	There are no (further) constraints on this element Element Id Observation.derivedFrom.identifier Short description Logical reference, when literal reference is not known Definition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. Comments When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation\|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). Data Type Identifier Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CX / EI (occasionally, more often EI maps to a resource id or a URL) rim:II - The Identifier class is a little looser than the v3 type II because it allows URIs as well as registered OIDs or GUIDs. Also maps to Role[classCode=IDENT] servd:Identifier rim:.identifier
use	Σ ?!	0..1	codeBinding	There are no (further) constraints on this element Element Id Observation.derivedFrom.identifier.use Short description usual \| official \| temp \| secondary \| old (If known) Definition The purpose of this identifier. Requirements Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Comments Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Data Type code Binding Identifies the purpose for this identifier, if known . IdentifierUse (required) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:N/A rim:Role.code or implied by context
type	Σ	0..1	CodeableConceptBinding	There are no (further) constraints on this element Element Id Observation.derivedFrom.identifier.type Short description Description of identifier Definition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Requirements Allows users to make use of identifiers when the identifier system is not known. Comments This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. Data Type CodeableConcept Binding A coded type for an identifier that can be used to determine which identifier to use for a specific purpose. Identifier Type Codes (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD v2:CX.5 rim:Role.code or implied by context
system	Σ	0..1	uri	There are no (further) constraints on this element Element Id Observation.derivedFrom.identifier.system Short description The namespace for the identifier value Definition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. Requirements There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Comments Identifier.system is always case sensitive. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General http://www.acme.com/identifiers/patient Mappings rim:n/a v2:CX.4 / EI-2-4 rim:II.root or Role.id.root servd:./IdentifierType
value	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.derivedFrom.identifier.value Short description The value that is unique Definition The portion of the identifier typically relevant to the user and which is unique within the context of the system. Comments If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General 123456 Mappings rim:n/a v2:CX.1 / EI.1 rim:II.extension or II.root if system indicates OID or GUID (Or Role.id.extension or root) servd:./Value
period	Σ I	0..1	Period	There are no (further) constraints on this element Element Id Observation.derivedFrom.identifier.period Short description Time period when id is/was valid for use Definition Time period during which identifier is/was valid for use. Comments A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. Data Type Period Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` per-1:If present, start SHALL have a lower value than end `start.hasValue().not() or end.hasValue().not() or (start <= end)` Mappings rim:n/a v2:DR rim:IVL<TS>[lowClosed="true" and highClosed="true"] or URG<TS>[lowClosed="true" and highClosed="true"] v2:CX.7 + CX.8 rim:Role.effectiveTime or implied by context servd:./StartDate and ./EndDate
assigner	Σ I	0..1	Reference(UK Core Organization)	There are no (further) constraints on this element Element Id Observation.derivedFrom.identifier.assigner Short description Organization that issued id (may be just text) Definition Organization that issued/manages the identifier. Comments The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Data Type Reference(UK Core Organization) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) v2:CX.4 / (CX.4,CX.9,CX.10) rim:II.assigningAuthorityName but note that this is an improper use by the definition of the field. Also Role.scoper servd:./IdentifierIssuingAuthority
display	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.derivedFrom.display Short description Text alternative for the resource Definition Plain text narrative that identifies the resource in addition to the resource reference. Comments This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
component	Σ	0..*	BackboneElement	There are no (further) constraints on this element Element Id Observation.component Short description Component results Definition Some observations have multiple component observations. These component observations are expressed as separate code value pairs that share the same attributes. Examples include systolic and diastolic component observations for blood pressure measurement and multiple component observations for genetics observations. Requirements Component observations share the same attributes in the Observation resource as the primary observation and are always treated a part of a single observation (they are not separable). However, the reference range for the primary observation value is not inherited by the component values and is required when appropriate for each component observation. Comments For a discussion on the ways Observations can be assembled in groups together see Notes below. Data Type BackboneElement Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:containment by OBX-4? rim:outBoundRelationship[typeCode=COMP]
code	Σ	1..1	CodeableConcept	There are no (further) constraints on this element Element Id Observation.component.code Short description Type of component observation (code / type) Definition Describes what was observed. Sometimes this is called the observation "code". Requirements Knowing what kind of observation is being made is essential to understanding the observation. Comments All code-value and component.code-component.value pairs need to be taken into account to correctly understand the meaning of the observation. Data Type CodeableConcept Binding Codes identifying names of simple observations. LOINCCodes (example) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD w5:FiveWs.what[x] sct-concept:< 363787002 \|Observable entity\| OR < 386053000 \|Evaluation procedure\| v2:OBX-3 rim:code
coding	Σ	0..*	Coding	There are no (further) constraints on this element Element Id Observation.component.code.coding Short description Code defined by a terminology system Definition A reference to a code defined by a terminology system. Requirements Allows for alternative encodings within a code system, and translations to other code systems. Comments Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. Data Type Coding Sliced: Unordered, Open, by code(Value), system(Value) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE subset one of the sets of component 1-3 or 4-6 rim:CV orim:fhir:Coding rdfs:subClassOf dt:CDCoding v2:CE.1-8, CE.10-22 rim:union(., ./translation) orim:fhir:CodeableConcept.coding rdfs:subPropertyOf dt:CD.coding
snomedCT	Σ	0..*	CodingBinding	There are no (further) constraints on this element Element Id Observation.component.code.coding:snomedCT Short description Code defined by a terminology system Definition A reference to a code defined by a terminology system. Requirements Allows for alternative encodings within a code system, and translations to other code systems. Comments Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. Data Type Coding Binding A code from the SNOMED Clinical Terminology UK coding system describing a type of observation UKCoreObservationType (preferred) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE subset one of the sets of component 1-3 or 4-6 rim:CV orim:fhir:Coding rdfs:subClassOf dt:CDCoding v2:CE.1-8, CE.10-22 rim:union(., ./translation) orim:fhir:CodeableConcept.coding rdfs:subPropertyOf dt:CD.coding
system	Σ	1..1	uriFixed Value	There are no (further) constraints on this element Element Id Observation.component.code.coding:snomedCT.system Short description Identity of the terminology system Definition The identification of the code system that defines the meaning of the symbol in the code. Requirements Need to be unambiguous about the source of the definition of the symbol. Comments The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Fixed Value http://snomed.info/sct Mappings rim:n/a v2:CE.3 rim:./codeSystem orim:*fhir:Coding.system rdfs:subPropertyOf dt:CDCoding.codeSystem
version	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.component.code.coding:snomedCT.version Short description Version of the system - if relevant Definition The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. Comments Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.7 rim:./codeSystemVersion orim:*fhir:Coding.version rdfs:subPropertyOf dt:CDCoding.codeSystemVersion
code	Σ	1..1	code	There are no (further) constraints on this element Element Id Observation.component.code.coding:snomedCT.code Short description Symbol in syntax defined by the system Definition A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). Requirements Need to refer to a particular code in the system. Comments Note that FHIR strings SHALL NOT exceed 1MB in size Data Type code Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.1 rim:./code orim:*fhir:Coding.code rdfs:subPropertyOf dt:CDCoding.code
display	Σ	1..1	string	There are no (further) constraints on this element Element Id Observation.component.code.coding:snomedCT.display Short description Representation defined by the system Definition A representation of the meaning of the code in the system, following the rules of the system. Requirements Need to be able to carry a human-readable meaning of the code for readers that do not know the system. Comments Note that FHIR strings SHALL NOT exceed 1MB in size Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.2 - but note this is not well followed rim:CV.displayName orim:*fhir:Coding.display rdfs:subPropertyOf dt:CDCoding.displayName
userSelected	Σ	0..1	boolean	There are no (further) constraints on this element Element Id Observation.component.code.coding:snomedCT.userSelected Short description If this coding was chosen directly by the user Definition Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). Requirements This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing. Comments Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. Data Type boolean Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:Sometimes implied by being first rim:CD.codingRationale orim:fhir:Coding.userSelected fhir:mapsTo dt:CDCoding.codingRationale. fhir:Coding.userSelected fhir:hasMap fhir:Coding.userSelected.map. fhir:Coding.userSelected.map a fhir:Map; fhir:target dt:CDCoding.codingRationale. fhir:Coding.userSelected\#true a [ fhir:source "true"; fhir:target dt:CDCoding.codingRationale\#O ]
text	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.component.code.text Short description Plain text representation of the concept Definition A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. Requirements The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source. Comments Very often the text is the same as a displayName of one of the codings. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.9. But note many systems use CE.2 for this rim:./originalText[mediaType/code="text/plain"]/data orim:fhir:CodeableConcept.text rdfs:subPropertyOf dt:CD.originalText
value[x]	Σ	0..1		There are no (further) constraints on this element Element Id Observation.component.value[x] Short description Actual component result Definition The information determined as a result of making the observation, if the information has a simple value. Requirements An observation exists to have a value, though it might not if it is in error, or if it represents a group of observations. Comments Used when observation has a set of component observations. An observation may have both a value (e.g. an Apgar score) and component observations (the observations from which the Apgar score was derived). If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the Notes section below. Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a sct-concept:363714003 \|Interprets\| < 441742003 \|Evaluation finding\| v2:OBX.2, OBX.5, OBX.6 rim:value sct-attr:363714003 \|Interprets\|
valueQuantity			Quantity	There are no (further) constraints on this element Data Type Quantity
valueCodeableConcept			CodeableConcept	There are no (further) constraints on this element Data Type CodeableConcept
valueString			string	There are no (further) constraints on this element Data Type string
valueBoolean			boolean	There are no (further) constraints on this element Data Type boolean
valueInteger			integer	There are no (further) constraints on this element Data Type integer
valueRange			Range	There are no (further) constraints on this element Data Type Range
valueRatio			Ratio	There are no (further) constraints on this element Data Type Ratio
valueSampledData			SampledData	There are no (further) constraints on this element Data Type SampledData
valueTime			time	There are no (further) constraints on this element Data Type time
valueDateTime			dateTime	There are no (further) constraints on this element Data Type dateTime
valuePeriod			Period	There are no (further) constraints on this element Data Type Period
dataAbsentReason	I	0..1	CodeableConceptBinding	There are no (further) constraints on this element Element Id Observation.component.dataAbsentReason Short description Why the component result is missing Definition Provides a reason why the expected value in the element Observation.component.value[x] is missing. Requirements For many results it is necessary to handle exceptional values in measurements. Comments "Null" or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "test not done". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Because of these options, use-case agreements are required to interpret general observations for exceptional values. Data Type CodeableConcept Binding Codes specifying why the result (`Observation.value[x]`) is missing. DataAbsentReason (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD v2:N/A rim:value.nullFlavor
interpretation		0..*	CodeableConceptBinding	There are no (further) constraints on this element Element Id Observation.component.interpretation Short description High, low, normal, etc. Alternate names Abnormal Flag Definition A categorical assessment of an observation value. For example, high, low, normal. Requirements For some results, particularly numeric results, an interpretation is necessary to fully understand the significance of a result. Comments Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. Data Type CodeableConcept Binding Codes identifying interpretations of observations. ObservationInterpretationCodes (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD sct-concept:< 260245000 \|Findings values\| v2:OBX-8 rim:interpretationCode sct-attr:363713009 \|Has interpretation\|
referenceRange		0..*	see (referenceRange)	There are no (further) constraints on this element Element Id Observation.component.referenceRange Short description Provides guide for interpretation of component result Definition Guidance on how to interpret the value by comparison to a normal or recommended range. Requirements Knowing what values are considered "normal" can help evaluate the significance of a particular result. Need to be able to provide multiple reference ranges for different contexts. Comments Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. Mappings v2:OBX.7 rim:outboundRelationship[typeCode=REFV]/target[classCode=OBS, moodCode=EVN]

from UK Core Observation

Observation	I		Observation	There are no (further) constraints on this element Element Id Observation Short description Measurements and simple assertions Alternate names Vital Signs, Measurement, Results, Tests Definition Measurements and simple assertions made about a patient, device or other subject. Comments Used for simple observations such as device measurements, laboratory atomic results, vital signs, height, weight, smoking status, comments, etc. Other resources are used to provide context for observations such as laboratory reports, etc. Data Type Observation Constraints dom-2:If the resource is contained in another resource, it SHALL NOT contain nested Resources `contained.contained.empty()` dom-4:If a resource is contained in another resource, it SHALL NOT have a meta.versionId or a meta.lastUpdated `contained.meta.versionId.empty() and contained.meta.lastUpdated.empty()` dom-3:If the resource is contained in another resource, it SHALL be referred to from elsewhere in the resource or SHALL refer to the containing resource `contained.where((('#'+id in (%resource.descendants().reference \| %resource.descendants().as(canonical) \| %resource.descendants().as(uri) \| %resource.descendants().as(url))) or descendants().where(reference = '#').exists() or descendants().where(as(canonical) = '#').exists() or descendants().where(as(canonical) = '#').exists()).not()).trace('unmatched', id).empty()` dom-6:A resource should have narrative for robust management text.`div`.exists() dom-5:If a resource is contained in another resource, it SHALL NOT have a security label `contained.meta.security.empty()` obs-7:If Observation.code is the same as an Observation.component.code then the value element associated with the code SHALL NOT be present `value.empty() or component.code.where(coding.intersect(%resource.code.coding).exists()).empty()` obs-6:dataAbsentReason SHALL only be present if Observation.value[x] is not present `dataAbsentReason.empty() or value.empty()` Mappings rim:Entity. Role, or Act workflow:Event sct-concept:< 363787002 \|Observable entity\| v2:OBX rim:Observation[classCode=OBS, moodCode=EVN]
extension	I	0..*	Extension	Element Id Observation.extension Short description Additional content defined by implementations Alternate names extensions, user content Definition May be used to represent additional information that is not part of the basic definition of the resource. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Comments There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Data Type Extension Sliced: Unordered, Open, by url(Value) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ext-1:Must have either extensions or value[x], not both `extension.exists() != value.exists()` Mappings rim:n/a rim:N/A
covid19Testing	S I	0..1	Extension(Complex)	Element Id Observation.extension:covid19Testing Short description Optional Extensions Element Alternate names extensions, user content Definition Optional Extension Element - found in all resources. Comments There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone. Data Type Extension(Complex) Extension URL https://fhir.nhs.uk/StructureDefinition/Extension-COVID19-TestResult Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ext-1:Must have either extensions or value[x], not both `extension.exists() != value.exists()` Mappings rim:n/a rim:N/A
identifier	S Σ	1..*	Identifier	Element Id Observation.identifier Short description Business Identifier for observation Definition A unique identifier assigned to this observation. For COVID-19 Test History this will be The identifier will be the specimen id. `"identifier": [ { "system": "https://fhir.nhs.uk/Id/SpecimenId", "value": "eb89a392-5b20-11eb-ae93-0242ac130002" } ],` Requirements Allows observations to be distinguished and referenced. Data Type Identifier Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CX / EI (occasionally, more often EI maps to a resource id or a URL) rim:II - The Identifier class is a little looser than the v3 type II because it allows URIs as well as registered OIDs or GUIDs. Also maps to Role[classCode=IDENT] servd:Identifier workflow:Event.identifier w5:FiveWs.identifier v2:OBX.21 For OBX segments from systems without OBX-21 support a combination of ORC/OBR and OBX must be negotiated between trading partners to uniquely identify the OBX segment. Depending on how V2 has been implemented each of these may be an option: 1) OBR-3 + OBX-3 + OBX-4 or 2) OBR-3 + OBR-4 + OBX-3 + OBX-4 or 2) some other way to uniquely ID the OBR/ORC + OBX-3 + OBX-4. rim:id
use	Σ ?!	0..1	codeBinding	There are no (further) constraints on this element Element Id Observation.identifier.use Short description usual \| official \| temp \| secondary \| old (If known) Definition The purpose of this identifier. Requirements Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Comments Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Data Type code Binding Identifies the purpose for this identifier, if known . IdentifierUse (required) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:N/A rim:Role.code or implied by context
type	Σ	0..1	CodeableConceptBinding	There are no (further) constraints on this element Element Id Observation.identifier.type Short description Description of identifier Definition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Requirements Allows users to make use of identifiers when the identifier system is not known. Comments This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. Data Type CodeableConcept Binding A coded type for an identifier that can be used to determine which identifier to use for a specific purpose. Identifier Type Codes (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD v2:CX.5 rim:Role.code or implied by context
system	Σ	1..1	uri	There are no (further) constraints on this element Element Id Observation.identifier.system Short description The namespace for the identifier value Definition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. Requirements There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Comments Identifier.system is always case sensitive. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General http://www.acme.com/identifiers/patient Mappings rim:n/a v2:CX.4 / EI-2-4 rim:II.root or Role.id.root servd:./IdentifierType
value	Σ	1..1	string	There are no (further) constraints on this element Element Id Observation.identifier.value Short description The value that is unique Definition The portion of the identifier typically relevant to the user and which is unique within the context of the system. Comments If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General 123456 Mappings rim:n/a v2:CX.1 / EI.1 rim:II.extension or II.root if system indicates OID or GUID (Or Role.id.extension or root) servd:./Value
period	Σ I	0..1	Period	There are no (further) constraints on this element Element Id Observation.identifier.period Short description Time period when id is/was valid for use Definition Time period during which identifier is/was valid for use. Comments A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. Data Type Period Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` per-1:If present, start SHALL have a lower value than end `start.hasValue().not() or end.hasValue().not() or (start <= end)` Mappings rim:n/a v2:DR rim:IVL<TS>[lowClosed="true" and highClosed="true"] or URG<TS>[lowClosed="true" and highClosed="true"] v2:CX.7 + CX.8 rim:Role.effectiveTime or implied by context servd:./StartDate and ./EndDate
assigner	Σ I	0..1	Reference(UK Core Organization)	There are no (further) constraints on this element Element Id Observation.identifier.assigner Short description Organization that issued id (may be just text) Definition Organization that issued/manages the identifier. Comments The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Data Type Reference(UK Core Organization) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) v2:CX.4 / (CX.4,CX.9,CX.10) rim:II.assigningAuthorityName but note that this is an improper use by the definition of the field. Also Role.scoper servd:./IdentifierIssuingAuthority
basedOn	Σ I	0..*	Reference(DeviceRequest \| ImmunizationRecommendation \| NutritionOrder \| UK Core CarePlan \| UK Core MedicationRequest \| UK Core ServiceRequest)	There are no (further) constraints on this element Element Id Observation.basedOn Short description Fulfills plan, proposal or order Alternate names Fulfills Definition A plan, proposal or order that is fulfilled in whole or in part by this event. For example, a MedicationRequest may require a patient to have laboratory test performed before it is dispensed. Requirements Allows tracing of authorization for the event and tracking whether proposals/recommendations were acted upon. Comments References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. Data Type Reference(DeviceRequest \| ImmunizationRecommendation \| NutritionOrder \| UK Core CarePlan \| UK Core MedicationRequest \| UK Core ServiceRequest) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) workflow:Event.basedOn v2:ORC rim:.inboundRelationship[typeCode=COMP].source[moodCode=EVN]
reference	Σ I	0..1	string	There are no (further) constraints on this element Element Id Observation.basedOn.reference Short description Literal reference, Relative, internal or absolute URL Definition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Comments Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
type	Σ	0..1	uriBinding	There are no (further) constraints on this element Element Id Observation.basedOn.type Short description Type the reference refers to (e.g. "Patient") Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). Comments This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Data Type uri Binding Aa resource (or, for logical models, the URI of the logical model). ResourceType (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
identifier	Σ	0..1	Identifier	There are no (further) constraints on this element Element Id Observation.basedOn.identifier Short description Logical reference, when literal reference is not known Definition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. Comments When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation\|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). Data Type Identifier Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CX / EI (occasionally, more often EI maps to a resource id or a URL) rim:II - The Identifier class is a little looser than the v3 type II because it allows URIs as well as registered OIDs or GUIDs. Also maps to Role[classCode=IDENT] servd:Identifier rim:.identifier
use	Σ ?!	0..1	codeBinding	There are no (further) constraints on this element Element Id Observation.basedOn.identifier.use Short description usual \| official \| temp \| secondary \| old (If known) Definition The purpose of this identifier. Requirements Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Comments Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Data Type code Binding Identifies the purpose for this identifier, if known . IdentifierUse (required) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:N/A rim:Role.code or implied by context
type	Σ	0..1	CodeableConceptBinding	There are no (further) constraints on this element Element Id Observation.basedOn.identifier.type Short description Description of identifier Definition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Requirements Allows users to make use of identifiers when the identifier system is not known. Comments This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. Data Type CodeableConcept Binding A coded type for an identifier that can be used to determine which identifier to use for a specific purpose. Identifier Type Codes (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD v2:CX.5 rim:Role.code or implied by context
system	Σ	0..1	uri	There are no (further) constraints on this element Element Id Observation.basedOn.identifier.system Short description The namespace for the identifier value Definition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. Requirements There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Comments Identifier.system is always case sensitive. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General http://www.acme.com/identifiers/patient Mappings rim:n/a v2:CX.4 / EI-2-4 rim:II.root or Role.id.root servd:./IdentifierType
value	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.basedOn.identifier.value Short description The value that is unique Definition The portion of the identifier typically relevant to the user and which is unique within the context of the system. Comments If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General 123456 Mappings rim:n/a v2:CX.1 / EI.1 rim:II.extension or II.root if system indicates OID or GUID (Or Role.id.extension or root) servd:./Value
period	Σ I	0..1	Period	There are no (further) constraints on this element Element Id Observation.basedOn.identifier.period Short description Time period when id is/was valid for use Definition Time period during which identifier is/was valid for use. Comments A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. Data Type Period Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` per-1:If present, start SHALL have a lower value than end `start.hasValue().not() or end.hasValue().not() or (start <= end)` Mappings rim:n/a v2:DR rim:IVL<TS>[lowClosed="true" and highClosed="true"] or URG<TS>[lowClosed="true" and highClosed="true"] v2:CX.7 + CX.8 rim:Role.effectiveTime or implied by context servd:./StartDate and ./EndDate
assigner	Σ I	0..1	Reference(UK Core Organization)	There are no (further) constraints on this element Element Id Observation.basedOn.identifier.assigner Short description Organization that issued id (may be just text) Definition Organization that issued/manages the identifier. Comments The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Data Type Reference(UK Core Organization) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) v2:CX.4 / (CX.4,CX.9,CX.10) rim:II.assigningAuthorityName but note that this is an improper use by the definition of the field. Also Role.scoper servd:./IdentifierIssuingAuthority
display	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.basedOn.display Short description Text alternative for the resource Definition Plain text narrative that identifies the resource in addition to the resource reference. Comments This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
partOf	Σ I	0..*	Reference(UK Core Imaging Study \| UK Core Immunization \| UK Core MedicationAdministration \| UK Core MedicationDispense \| UK Core MedicationStatement \| UK Core Procedure)	There are no (further) constraints on this element Element Id Observation.partOf Short description Part of referenced event Alternate names Container Definition A larger event of which this particular Observation is a component or step. For example, an observation as part of a procedure. Comments To link an Observation to an Encounter use `encounter`. See the Notes below for guidance on referencing another Observation. Data Type Reference(UK Core Imaging Study \| UK Core Immunization \| UK Core MedicationAdministration \| UK Core MedicationDispense \| UK Core MedicationStatement \| UK Core Procedure) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) workflow:Event.partOf v2:Varies by domain rim:.outboundRelationship[typeCode=FLFS].target
reference	Σ I	0..1	string	There are no (further) constraints on this element Element Id Observation.partOf.reference Short description Literal reference, Relative, internal or absolute URL Definition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Comments Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
type	Σ	0..1	uriBinding	There are no (further) constraints on this element Element Id Observation.partOf.type Short description Type the reference refers to (e.g. "Patient") Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). Comments This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Data Type uri Binding Aa resource (or, for logical models, the URI of the logical model). ResourceType (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
identifier	Σ	0..1	Identifier	There are no (further) constraints on this element Element Id Observation.partOf.identifier Short description Logical reference, when literal reference is not known Definition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. Comments When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation\|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). Data Type Identifier Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CX / EI (occasionally, more often EI maps to a resource id or a URL) rim:II - The Identifier class is a little looser than the v3 type II because it allows URIs as well as registered OIDs or GUIDs. Also maps to Role[classCode=IDENT] servd:Identifier rim:.identifier
use	Σ ?!	0..1	codeBinding	There are no (further) constraints on this element Element Id Observation.partOf.identifier.use Short description usual \| official \| temp \| secondary \| old (If known) Definition The purpose of this identifier. Requirements Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Comments Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Data Type code Binding Identifies the purpose for this identifier, if known . IdentifierUse (required) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:N/A rim:Role.code or implied by context
type	Σ	0..1	CodeableConceptBinding	There are no (further) constraints on this element Element Id Observation.partOf.identifier.type Short description Description of identifier Definition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Requirements Allows users to make use of identifiers when the identifier system is not known. Comments This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. Data Type CodeableConcept Binding A coded type for an identifier that can be used to determine which identifier to use for a specific purpose. Identifier Type Codes (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD v2:CX.5 rim:Role.code or implied by context
system	Σ	0..1	uri	There are no (further) constraints on this element Element Id Observation.partOf.identifier.system Short description The namespace for the identifier value Definition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. Requirements There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Comments Identifier.system is always case sensitive. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General http://www.acme.com/identifiers/patient Mappings rim:n/a v2:CX.4 / EI-2-4 rim:II.root or Role.id.root servd:./IdentifierType
value	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.partOf.identifier.value Short description The value that is unique Definition The portion of the identifier typically relevant to the user and which is unique within the context of the system. Comments If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General 123456 Mappings rim:n/a v2:CX.1 / EI.1 rim:II.extension or II.root if system indicates OID or GUID (Or Role.id.extension or root) servd:./Value
period	Σ I	0..1	Period	There are no (further) constraints on this element Element Id Observation.partOf.identifier.period Short description Time period when id is/was valid for use Definition Time period during which identifier is/was valid for use. Comments A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. Data Type Period Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` per-1:If present, start SHALL have a lower value than end `start.hasValue().not() or end.hasValue().not() or (start <= end)` Mappings rim:n/a v2:DR rim:IVL<TS>[lowClosed="true" and highClosed="true"] or URG<TS>[lowClosed="true" and highClosed="true"] v2:CX.7 + CX.8 rim:Role.effectiveTime or implied by context servd:./StartDate and ./EndDate
assigner	Σ I	0..1	Reference(UK Core Organization)	There are no (further) constraints on this element Element Id Observation.partOf.identifier.assigner Short description Organization that issued id (may be just text) Definition Organization that issued/manages the identifier. Comments The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Data Type Reference(UK Core Organization) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) v2:CX.4 / (CX.4,CX.9,CX.10) rim:II.assigningAuthorityName but note that this is an improper use by the definition of the field. Also Role.scoper servd:./IdentifierIssuingAuthority
display	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.partOf.display Short description Text alternative for the resource Definition Plain text narrative that identifies the resource in addition to the resource reference. Comments This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
status	S Σ ?!	1..1	codeBinding	Element Id Observation.status Short description registered \| preliminary \| final \| amended + Definition The status of the result value. For COVID-19 Test History the status of the observation will always be `final` `"status": "final",` Requirements Need to track the status of individual results. Some results are finalized before the whole report is finalized. Comments This element is labeled as a modifier because the status contains codes that mark the resource as not currently valid. Data Type code Binding Codes providing the status of an observation. ObservationStatus (required) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a workflow:Event.status w5:FiveWs.status sct-concept:< 445584004 \|Report by finality status\| v2:OBX-11 rim:status Amended & Final are differentiated by whether it is the subject of a ControlAct event with a type of "revise"
category	S	0..*	CodeableConceptBinding	Element Id Observation.category Short description Classification of type of observation Definition This is an optional element. If used the category will always be `laboratory` `"category": [ { "coding": [ { "system": "http://terminology.hl7.org/CodeSystem/observation-category", "code": "laboratory", "display": "Laboratory" } ], "text": "Laboratory" } ],` For COVID-19 Tests, the ValueSet SHOULD be used to indicate which test pillar the observation originated. `"category": [ { "coding": [ { "system": "https://fhir.nhs.uk/CodeSystem/covid-test-pillar", "code": "pillar-1", "display": "pillar 1" } ] } ],` Requirements Used for filtering what observations are retrieved and displayed. Comments In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set. Data Type CodeableConcept Sliced: Unordered, Open, by coding.system(Value) Binding Codes for high level observation categories. ObservationCategory (required) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD w5:FiveWs.class rim:.outboundRelationship[typeCode="COMP].target[classCode="LIST", moodCode="EVN"].code
(All Slices)				There are no (further) constraints on this element
coding	Σ	1..*	Coding	There are no (further) constraints on this element Element Id Observation.category.coding Short description Code defined by a terminology system Definition A reference to a code defined by a terminology system. Requirements Allows for alternative encodings within a code system, and translations to other code systems. Comments Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. Data Type Coding Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE subset one of the sets of component 1-3 or 4-6 rim:CV orim:fhir:Coding rdfs:subClassOf dt:CDCoding v2:CE.1-8, CE.10-22 rim:union(., ./translation) orim:fhir:CodeableConcept.coding rdfs:subPropertyOf dt:CD.coding
system	S Σ	1..1	uri	There are no (further) constraints on this element Element Id Observation.category.coding.system Short description Identity of the terminology system Definition The identification of the code system that defines the meaning of the symbol in the code. Requirements Need to be unambiguous about the source of the definition of the symbol. Comments The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.3 rim:./codeSystem orim:*fhir:Coding.system rdfs:subPropertyOf dt:CDCoding.codeSystem
version	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.category.coding.version Short description Version of the system - if relevant Definition The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. Comments Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.7 rim:./codeSystemVersion orim:*fhir:Coding.version rdfs:subPropertyOf dt:CDCoding.codeSystemVersion
code	S Σ	1..1	code	There are no (further) constraints on this element Element Id Observation.category.coding.code Short description Symbol in syntax defined by the system Definition A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). Requirements Need to refer to a particular code in the system. Comments Note that FHIR strings SHALL NOT exceed 1MB in size Data Type code Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.1 rim:./code orim:*fhir:Coding.code rdfs:subPropertyOf dt:CDCoding.code
display	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.category.coding.display Short description Representation defined by the system Definition A representation of the meaning of the code in the system, following the rules of the system. Requirements Need to be able to carry a human-readable meaning of the code for readers that do not know the system. Comments Note that FHIR strings SHALL NOT exceed 1MB in size Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.2 - but note this is not well followed rim:CV.displayName orim:*fhir:Coding.display rdfs:subPropertyOf dt:CDCoding.displayName
userSelected	Σ	0..1	boolean	There are no (further) constraints on this element Element Id Observation.category.coding.userSelected Short description If this coding was chosen directly by the user Definition Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). Requirements This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing. Comments Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. Data Type boolean Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:Sometimes implied by being first rim:CD.codingRationale orim:fhir:Coding.userSelected fhir:mapsTo dt:CDCoding.codingRationale. fhir:Coding.userSelected fhir:hasMap fhir:Coding.userSelected.map. fhir:Coding.userSelected.map a fhir:Map; fhir:target dt:CDCoding.codingRationale. fhir:Coding.userSelected\#true a [ fhir:source "true"; fhir:target dt:CDCoding.codingRationale\#O ]
text	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.category.text Short description Plain text representation of the concept Definition A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. Requirements The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source. Comments Very often the text is the same as a displayName of one of the codings. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.9. But note many systems use CE.2 for this rim:./originalText[mediaType/code="text/plain"]/data orim:fhir:CodeableConcept.text rdfs:subPropertyOf dt:CD.originalText
COVID-TestPillar		0..1	CodeableConceptBinding	Element Id Observation.category:COVID-TestPillar Short description Classification of type of observation Definition A code that classifies the general type of observation being made. Requirements Used for filtering what observations are retrieved and displayed. Comments In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set. Data Type CodeableConcept Binding Codes for high level observation categories. ObservationCategoryCodes (preferred) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD w5:FiveWs.class rim:.outboundRelationship[typeCode="COMP].target[classCode="LIST", moodCode="EVN"].code
coding	Σ	0..*	Coding	There are no (further) constraints on this element Element Id Observation.category:COVID-TestPillar.coding Short description Code defined by a terminology system Definition A reference to a code defined by a terminology system. Requirements Allows for alternative encodings within a code system, and translations to other code systems. Comments Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. Data Type Coding Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE subset one of the sets of component 1-3 or 4-6 rim:CV orim:fhir:Coding rdfs:subClassOf dt:CDCoding v2:CE.1-8, CE.10-22 rim:union(., ./translation) orim:fhir:CodeableConcept.coding rdfs:subPropertyOf dt:CD.coding
system	Σ	0..1	uriFixed Value	Element Id Observation.category:COVID-TestPillar.coding.system Short description Identity of the terminology system Definition The identification of the code system that defines the meaning of the symbol in the code. Requirements Need to be unambiguous about the source of the definition of the symbol. Comments The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Fixed Value https://fhir.nhs.uk/CodeSystem/covid-test-pillar Mappings rim:n/a v2:CE.3 rim:./codeSystem orim:*fhir:Coding.system rdfs:subPropertyOf dt:CDCoding.codeSystem
version	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.category:COVID-TestPillar.coding.version Short description Version of the system - if relevant Definition The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. Comments Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.7 rim:./codeSystemVersion orim:*fhir:Coding.version rdfs:subPropertyOf dt:CDCoding.codeSystemVersion
code	Σ	0..1	code	There are no (further) constraints on this element Element Id Observation.category:COVID-TestPillar.coding.code Short description Symbol in syntax defined by the system Definition A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). Requirements Need to refer to a particular code in the system. Comments Note that FHIR strings SHALL NOT exceed 1MB in size Data Type code Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.1 rim:./code orim:*fhir:Coding.code rdfs:subPropertyOf dt:CDCoding.code
display	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.category:COVID-TestPillar.coding.display Short description Representation defined by the system Definition A representation of the meaning of the code in the system, following the rules of the system. Requirements Need to be able to carry a human-readable meaning of the code for readers that do not know the system. Comments Note that FHIR strings SHALL NOT exceed 1MB in size Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.2 - but note this is not well followed rim:CV.displayName orim:*fhir:Coding.display rdfs:subPropertyOf dt:CDCoding.displayName
userSelected	Σ	0..1	boolean	There are no (further) constraints on this element Element Id Observation.category:COVID-TestPillar.coding.userSelected Short description If this coding was chosen directly by the user Definition Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). Requirements This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing. Comments Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. Data Type boolean Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:Sometimes implied by being first rim:CD.codingRationale orim:fhir:Coding.userSelected fhir:mapsTo dt:CDCoding.codingRationale. fhir:Coding.userSelected fhir:hasMap fhir:Coding.userSelected.map. fhir:Coding.userSelected.map a fhir:Map; fhir:target dt:CDCoding.codingRationale. fhir:Coding.userSelected\#true a [ fhir:source "true"; fhir:target dt:CDCoding.codingRationale\#O ]
text	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.category:COVID-TestPillar.text Short description Plain text representation of the concept Definition A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. Requirements The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source. Comments Very often the text is the same as a displayName of one of the codings. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.9. But note many systems use CE.2 for this rim:./originalText[mediaType/code="text/plain"]/data orim:fhir:CodeableConcept.text rdfs:subPropertyOf dt:CD.originalText
UKCoreCategory		0..*	CodeableConceptBinding	Element Id Observation.category:UKCoreCategory Short description Classification of type of observation Definition A code that classifies the general type of observation being made. Requirements Used for filtering what observations are retrieved and displayed. Comments In addition to the required category valueset, this element allows various categorization schemes based on the owner’s definition of the category and effectively multiple categories can be used at once. The level of granularity is defined by the category concepts in the value set. Data Type CodeableConcept Binding Codes for high level observation categories. ObservationCategoryCodes (preferred) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD w5:FiveWs.class rim:.outboundRelationship[typeCode="COMP].target[classCode="LIST", moodCode="EVN"].code
coding	Σ	0..*	Coding	There are no (further) constraints on this element Element Id Observation.category:UKCoreCategory.coding Short description Code defined by a terminology system Definition A reference to a code defined by a terminology system. Requirements Allows for alternative encodings within a code system, and translations to other code systems. Comments Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. Data Type Coding Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE subset one of the sets of component 1-3 or 4-6 rim:CV orim:fhir:Coding rdfs:subClassOf dt:CDCoding v2:CE.1-8, CE.10-22 rim:union(., ./translation) orim:fhir:CodeableConcept.coding rdfs:subPropertyOf dt:CD.coding
system	Σ	0..1	uriFixed Value	Element Id Observation.category:UKCoreCategory.coding.system Short description Identity of the terminology system Definition The identification of the code system that defines the meaning of the symbol in the code. Requirements Need to be unambiguous about the source of the definition of the symbol. Comments The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Fixed Value http://terminology.hl7.org/CodeSystem/observation-category Mappings rim:n/a v2:CE.3 rim:./codeSystem orim:*fhir:Coding.system rdfs:subPropertyOf dt:CDCoding.codeSystem
version	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.category:UKCoreCategory.coding.version Short description Version of the system - if relevant Definition The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. Comments Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.7 rim:./codeSystemVersion orim:*fhir:Coding.version rdfs:subPropertyOf dt:CDCoding.codeSystemVersion
code	Σ	0..1	code	There are no (further) constraints on this element Element Id Observation.category:UKCoreCategory.coding.code Short description Symbol in syntax defined by the system Definition A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). Requirements Need to refer to a particular code in the system. Comments Note that FHIR strings SHALL NOT exceed 1MB in size Data Type code Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.1 rim:./code orim:*fhir:Coding.code rdfs:subPropertyOf dt:CDCoding.code
display	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.category:UKCoreCategory.coding.display Short description Representation defined by the system Definition A representation of the meaning of the code in the system, following the rules of the system. Requirements Need to be able to carry a human-readable meaning of the code for readers that do not know the system. Comments Note that FHIR strings SHALL NOT exceed 1MB in size Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.2 - but note this is not well followed rim:CV.displayName orim:*fhir:Coding.display rdfs:subPropertyOf dt:CDCoding.displayName
userSelected	Σ	0..1	boolean	There are no (further) constraints on this element Element Id Observation.category:UKCoreCategory.coding.userSelected Short description If this coding was chosen directly by the user Definition Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). Requirements This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing. Comments Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. Data Type boolean Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:Sometimes implied by being first rim:CD.codingRationale orim:fhir:Coding.userSelected fhir:mapsTo dt:CDCoding.codingRationale. fhir:Coding.userSelected fhir:hasMap fhir:Coding.userSelected.map. fhir:Coding.userSelected.map a fhir:Map; fhir:target dt:CDCoding.codingRationale. fhir:Coding.userSelected\#true a [ fhir:source "true"; fhir:target dt:CDCoding.codingRationale\#O ]
text	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.category:UKCoreCategory.text Short description Plain text representation of the concept Definition A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. Requirements The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source. Comments Very often the text is the same as a displayName of one of the codings. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.9. But note many systems use CE.2 for this rim:./originalText[mediaType/code="text/plain"]/data orim:fhir:CodeableConcept.text rdfs:subPropertyOf dt:CD.originalText
code	S Σ	1..1	CodeableConcept	Element Id Observation.code Short description Type of observation (code / type) Alternate names Name Definition Type of observation, for COVID-10 see Observation Definition for `code` values. `"code": { "coding": [ { "system": "http://snomed.info/sct", "code": "871555000", "display": "Detection of ribonucleic acid of Severe acute respiratory syndrome coronavirus 2" } ] },` Requirements Knowing what kind of observation is being made is essential to understanding the observation. Comments All code-value and, if present, component.code-component.value pairs need to be taken into account to correctly understand the meaning of the observation. Data Type CodeableConcept Binding Codes identifying names of simple observations. LOINCCodes (example) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD workflow:Event.code w5:FiveWs.what[x] sct-concept:< 363787002 \|Observable entity\| OR < 386053000 \|Evaluation procedure\| v2:OBX-3 rim:code sct-attr:116680003 \|Is a\|
coding	Σ	0..*	Coding	There are no (further) constraints on this element Element Id Observation.code.coding Short description Code defined by a terminology system Definition A reference to a code defined by a terminology system. Requirements Allows for alternative encodings within a code system, and translations to other code systems. Comments Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. Data Type Coding Sliced: Unordered, Open, by system(Value) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE subset one of the sets of component 1-3 or 4-6 rim:CV orim:fhir:Coding rdfs:subClassOf dt:CDCoding v2:CE.1-8, CE.10-22 rim:union(., ./translation) orim:fhir:CodeableConcept.coding rdfs:subPropertyOf dt:CD.coding
snomedCT	Σ	0..*	CodingBinding	There are no (further) constraints on this element Element Id Observation.code.coding:snomedCT Short description Code defined by a terminology system Definition A reference to a code defined by a terminology system. Requirements Allows for alternative encodings within a code system, and translations to other code systems. Comments Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. Data Type Coding Binding A code from the SNOMED Clinical Terminology UK coding system describing a type of observation UKCoreObservationType (preferred) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE subset one of the sets of component 1-3 or 4-6 rim:CV orim:fhir:Coding rdfs:subClassOf dt:CDCoding v2:CE.1-8, CE.10-22 rim:union(., ./translation) orim:fhir:CodeableConcept.coding rdfs:subPropertyOf dt:CD.coding
system	Σ	1..1	uriFixed Value	There are no (further) constraints on this element Element Id Observation.code.coding:snomedCT.system Short description Identity of the terminology system Definition The identification of the code system that defines the meaning of the symbol in the code. Requirements Need to be unambiguous about the source of the definition of the symbol. Comments The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Fixed Value http://snomed.info/sct Mappings rim:n/a v2:CE.3 rim:./codeSystem orim:*fhir:Coding.system rdfs:subPropertyOf dt:CDCoding.codeSystem
version	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.code.coding:snomedCT.version Short description Version of the system - if relevant Definition The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. Comments Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.7 rim:./codeSystemVersion orim:*fhir:Coding.version rdfs:subPropertyOf dt:CDCoding.codeSystemVersion
code	Σ	1..1	code	There are no (further) constraints on this element Element Id Observation.code.coding:snomedCT.code Short description Symbol in syntax defined by the system Definition A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). Requirements Need to refer to a particular code in the system. Comments Note that FHIR strings SHALL NOT exceed 1MB in size Data Type code Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.1 rim:./code orim:*fhir:Coding.code rdfs:subPropertyOf dt:CDCoding.code
display	Σ	1..1	string	There are no (further) constraints on this element Element Id Observation.code.coding:snomedCT.display Short description Representation defined by the system Definition A representation of the meaning of the code in the system, following the rules of the system. Requirements Need to be able to carry a human-readable meaning of the code for readers that do not know the system. Comments Note that FHIR strings SHALL NOT exceed 1MB in size Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.2 - but note this is not well followed rim:CV.displayName orim:*fhir:Coding.display rdfs:subPropertyOf dt:CDCoding.displayName
userSelected	Σ	0..1	boolean	There are no (further) constraints on this element Element Id Observation.code.coding:snomedCT.userSelected Short description If this coding was chosen directly by the user Definition Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). Requirements This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing. Comments Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. Data Type boolean Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:Sometimes implied by being first rim:CD.codingRationale orim:fhir:Coding.userSelected fhir:mapsTo dt:CDCoding.codingRationale. fhir:Coding.userSelected fhir:hasMap fhir:Coding.userSelected.map. fhir:Coding.userSelected.map a fhir:Map; fhir:target dt:CDCoding.codingRationale. fhir:Coding.userSelected\#true a [ fhir:source "true"; fhir:target dt:CDCoding.codingRationale\#O ]
loinc	Σ	0..*	Coding	There are no (further) constraints on this element Element Id Observation.code.coding:loinc Short description Code defined by a terminology system Definition A reference to a code defined by a terminology system. Requirements Allows for alternative encodings within a code system, and translations to other code systems. Comments Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. Data Type Coding Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE subset one of the sets of component 1-3 or 4-6 rim:CV orim:fhir:Coding rdfs:subClassOf dt:CDCoding v2:CE.1-8, CE.10-22 rim:union(., ./translation) orim:fhir:CodeableConcept.coding rdfs:subPropertyOf dt:CD.coding
system	Σ	1..1	uriFixed Value	There are no (further) constraints on this element Element Id Observation.code.coding:loinc.system Short description Identity of the terminology system Definition The identification of the code system that defines the meaning of the symbol in the code. Requirements Need to be unambiguous about the source of the definition of the symbol. Comments The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Fixed Value http://loinc.org Mappings rim:n/a v2:CE.3 rim:./codeSystem orim:*fhir:Coding.system rdfs:subPropertyOf dt:CDCoding.codeSystem
version	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.code.coding:loinc.version Short description Version of the system - if relevant Definition The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. Comments Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.7 rim:./codeSystemVersion orim:*fhir:Coding.version rdfs:subPropertyOf dt:CDCoding.codeSystemVersion
code	Σ	1..1	code	There are no (further) constraints on this element Element Id Observation.code.coding:loinc.code Short description Symbol in syntax defined by the system Definition A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). Requirements Need to refer to a particular code in the system. Comments Note that FHIR strings SHALL NOT exceed 1MB in size Data Type code Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.1 rim:./code orim:*fhir:Coding.code rdfs:subPropertyOf dt:CDCoding.code
display	Σ	1..1	string	There are no (further) constraints on this element Element Id Observation.code.coding:loinc.display Short description Representation defined by the system Definition A representation of the meaning of the code in the system, following the rules of the system. Requirements Need to be able to carry a human-readable meaning of the code for readers that do not know the system. Comments Note that FHIR strings SHALL NOT exceed 1MB in size Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.2 - but note this is not well followed rim:CV.displayName orim:*fhir:Coding.display rdfs:subPropertyOf dt:CDCoding.displayName
userSelected	Σ	0..1	boolean	There are no (further) constraints on this element Element Id Observation.code.coding:loinc.userSelected Short description If this coding was chosen directly by the user Definition Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). Requirements This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing. Comments Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. Data Type boolean Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:Sometimes implied by being first rim:CD.codingRationale orim:fhir:Coding.userSelected fhir:mapsTo dt:CDCoding.codingRationale. fhir:Coding.userSelected fhir:hasMap fhir:Coding.userSelected.map. fhir:Coding.userSelected.map a fhir:Map; fhir:target dt:CDCoding.codingRationale. fhir:Coding.userSelected\#true a [ fhir:source "true"; fhir:target dt:CDCoding.codingRationale\#O ]
text	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.code.text Short description Plain text representation of the concept Definition A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. Requirements The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source. Comments Very often the text is the same as a displayName of one of the codings. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.9. But note many systems use CE.2 for this rim:./originalText[mediaType/code="text/plain"]/data orim:fhir:CodeableConcept.text rdfs:subPropertyOf dt:CD.originalText
subject	S Σ I	1..1	Reference(Group \| UK Core Device \| UK Core Location \| NHSDigitalPatientMinimal)	Element Id Observation.subject Short description Who and/or what the observation is about Definition The NHS Number will be an identifier reference which can be used with PDS FHIR API to return Patient demographics. If a local Patient is available, a reference to this will be present (e.g. "Patient/123") `"subject": { "reference": "Patient/123", "identifier": [ { "system": "https://fhir.nhs.uk/Id/nhs-number", "value": "987123456" } ] },` Requirements Observations have no value if you don't know who or what they're about. Comments One would expect this element to be a cardinality of 1..1. The only circumstance in which the subject can be missing is when the observation is made by a device that does not know the patient. In this case, the observation SHALL be matched to a patient through some context/channel matching technique, and at this point, the observation should be updated. Data Type Reference(Group \| UK Core Device \| UK Core Location \| NHSDigitalPatientMinimal) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` patient-reference:subject - An identifier reference or resource reference must be provided `(reference.exists() or (identifier.exists()))` patient-nhs:Supplied NHS Number is outside the English and Welsh NHS Number range or length of the number is wrong. `identifier.where(system='https://fhir.nhs.uk/Id/nhs-number').exists().not() or (identifier.where(system='https://fhir.nhs.uk/Id/nhs-number').exists() and identifier.where(system='https://fhir.nhs.uk/Id/nhs-number').value.matches('^([456789]{1}[0-9]{9})$'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) workflow:Event.subject w5:FiveWs.subject[x] v2:PID-3 rim:participation[typeCode=RTGT] w5:FiveWs.subject
reference	Σ I	0..1	string	There are no (further) constraints on this element Element Id Observation.subject.reference Short description Literal reference, Relative, internal or absolute URL Definition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Comments Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
type	Σ	0..1	uriBinding	There are no (further) constraints on this element Element Id Observation.subject.type Short description Type the reference refers to (e.g. "Patient") Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). Comments This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Data Type uri Binding Aa resource (or, for logical models, the URI of the logical model). ResourceType (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
identifier	Σ	0..1	Identifier	There are no (further) constraints on this element Element Id Observation.subject.identifier Short description Logical reference, when literal reference is not known Definition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. Comments When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation\|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). Data Type Identifier Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CX / EI (occasionally, more often EI maps to a resource id or a URL) rim:II - The Identifier class is a little looser than the v3 type II because it allows URIs as well as registered OIDs or GUIDs. Also maps to Role[classCode=IDENT] servd:Identifier rim:.identifier
use	Σ ?!	0..1	codeBinding	There are no (further) constraints on this element Element Id Observation.subject.identifier.use Short description usual \| official \| temp \| secondary \| old (If known) Definition The purpose of this identifier. Requirements Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Comments Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Data Type code Binding Identifies the purpose for this identifier, if known . IdentifierUse (required) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:N/A rim:Role.code or implied by context
type	Σ	0..1	CodeableConceptBinding	There are no (further) constraints on this element Element Id Observation.subject.identifier.type Short description Description of identifier Definition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Requirements Allows users to make use of identifiers when the identifier system is not known. Comments This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. Data Type CodeableConcept Binding A coded type for an identifier that can be used to determine which identifier to use for a specific purpose. Identifier Type Codes (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD v2:CX.5 rim:Role.code or implied by context
system	Σ	1..1	uriFixed Value	Element Id Observation.subject.identifier.system Short description The namespace for the identifier value Definition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. Requirements There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Comments Identifier.system is always case sensitive. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Fixed Value https://fhir.nhs.uk/Id/nhs-number Mappings rim:n/a v2:CX.4 / EI-2-4 rim:II.root or Role.id.root servd:./IdentifierType
value	Σ	1..1	string	There are no (further) constraints on this element Element Id Observation.subject.identifier.value Short description The value that is unique Definition The portion of the identifier typically relevant to the user and which is unique within the context of the system. Comments If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General 123456 Mappings rim:n/a v2:CX.1 / EI.1 rim:II.extension or II.root if system indicates OID or GUID (Or Role.id.extension or root) servd:./Value
period	Σ I	0..1	Period	There are no (further) constraints on this element Element Id Observation.subject.identifier.period Short description Time period when id is/was valid for use Definition Time period during which identifier is/was valid for use. Comments A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. Data Type Period Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` per-1:If present, start SHALL have a lower value than end `start.hasValue().not() or end.hasValue().not() or (start <= end)` Mappings rim:n/a v2:DR rim:IVL<TS>[lowClosed="true" and highClosed="true"] or URG<TS>[lowClosed="true" and highClosed="true"] v2:CX.7 + CX.8 rim:Role.effectiveTime or implied by context servd:./StartDate and ./EndDate
assigner	Σ I	0..1	Reference(UK Core Organization)	There are no (further) constraints on this element Element Id Observation.subject.identifier.assigner Short description Organization that issued id (may be just text) Definition Organization that issued/manages the identifier. Comments The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Data Type Reference(UK Core Organization) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) v2:CX.4 / (CX.4,CX.9,CX.10) rim:II.assigningAuthorityName but note that this is an improper use by the definition of the field. Also Role.scoper servd:./IdentifierIssuingAuthority
display	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.subject.display Short description Text alternative for the resource Definition Plain text narrative that identifies the resource in addition to the resource reference. Comments This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
focus	Σ I	0..*	Reference(Resource)	There are no (further) constraints on this element Element Id Observation.focus Short description What the observation is about, when it is not about the subject of record Definition The actual focus of an observation when it is not the patient of record representing something or someone associated with the patient such as a spouse, parent, fetus, or donor. For example, fetus observations in a mother's record. The focus of an observation could also be an existing condition, an intervention, the subject's diet, another observation of the subject, or a body structure such as tumor or implanted device. An example use case would be using the Observation resource to capture whether the mother is trained to change her child's tracheostomy tube. In this example, the child is the patient of record and the mother is the focus. Comments Typically, an observation is made about the subject - a patient, or group of patients, location, or device - and the distinction between the subject and what is directly measured for an observation is specified in the observation code itself ( e.g., "Blood Glucose") and does not need to be represented separately using this element. Use `specimen` if a reference to a specimen is required. If a code is required instead of a resource use either `bodysite` for bodysites or the standard extension focusCode. Data Type Reference(Resource) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) w5:FiveWs.subject[x] v2:OBX-3 rim:participation[typeCode=SBJ] w5:FiveWs.subject
reference	Σ I	0..1	string	There are no (further) constraints on this element Element Id Observation.focus.reference Short description Literal reference, Relative, internal or absolute URL Definition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Comments Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
type	Σ	0..1	uriBinding	There are no (further) constraints on this element Element Id Observation.focus.type Short description Type the reference refers to (e.g. "Patient") Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). Comments This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Data Type uri Binding Aa resource (or, for logical models, the URI of the logical model). ResourceType (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
identifier	Σ	0..1	Identifier	There are no (further) constraints on this element Element Id Observation.focus.identifier Short description Logical reference, when literal reference is not known Definition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. Comments When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation\|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). Data Type Identifier Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CX / EI (occasionally, more often EI maps to a resource id or a URL) rim:II - The Identifier class is a little looser than the v3 type II because it allows URIs as well as registered OIDs or GUIDs. Also maps to Role[classCode=IDENT] servd:Identifier rim:.identifier
use	Σ ?!	0..1	codeBinding	There are no (further) constraints on this element Element Id Observation.focus.identifier.use Short description usual \| official \| temp \| secondary \| old (If known) Definition The purpose of this identifier. Requirements Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Comments Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Data Type code Binding Identifies the purpose for this identifier, if known . IdentifierUse (required) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:N/A rim:Role.code or implied by context
type	Σ	0..1	CodeableConceptBinding	There are no (further) constraints on this element Element Id Observation.focus.identifier.type Short description Description of identifier Definition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Requirements Allows users to make use of identifiers when the identifier system is not known. Comments This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. Data Type CodeableConcept Binding A coded type for an identifier that can be used to determine which identifier to use for a specific purpose. Identifier Type Codes (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD v2:CX.5 rim:Role.code or implied by context
system	Σ	0..1	uri	There are no (further) constraints on this element Element Id Observation.focus.identifier.system Short description The namespace for the identifier value Definition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. Requirements There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Comments Identifier.system is always case sensitive. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General http://www.acme.com/identifiers/patient Mappings rim:n/a v2:CX.4 / EI-2-4 rim:II.root or Role.id.root servd:./IdentifierType
value	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.focus.identifier.value Short description The value that is unique Definition The portion of the identifier typically relevant to the user and which is unique within the context of the system. Comments If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General 123456 Mappings rim:n/a v2:CX.1 / EI.1 rim:II.extension or II.root if system indicates OID or GUID (Or Role.id.extension or root) servd:./Value
period	Σ I	0..1	Period	There are no (further) constraints on this element Element Id Observation.focus.identifier.period Short description Time period when id is/was valid for use Definition Time period during which identifier is/was valid for use. Comments A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. Data Type Period Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` per-1:If present, start SHALL have a lower value than end `start.hasValue().not() or end.hasValue().not() or (start <= end)` Mappings rim:n/a v2:DR rim:IVL<TS>[lowClosed="true" and highClosed="true"] or URG<TS>[lowClosed="true" and highClosed="true"] v2:CX.7 + CX.8 rim:Role.effectiveTime or implied by context servd:./StartDate and ./EndDate
assigner	Σ I	0..1	Reference(UK Core Organization)	There are no (further) constraints on this element Element Id Observation.focus.identifier.assigner Short description Organization that issued id (may be just text) Definition Organization that issued/manages the identifier. Comments The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Data Type Reference(UK Core Organization) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) v2:CX.4 / (CX.4,CX.9,CX.10) rim:II.assigningAuthorityName but note that this is an improper use by the definition of the field. Also Role.scoper servd:./IdentifierIssuingAuthority
display	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.focus.display Short description Text alternative for the resource Definition Plain text narrative that identifies the resource in addition to the resource reference. Comments This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
encounter	Σ I	0..1	Reference(UK Core Encounter)	There are no (further) constraints on this element Element Id Observation.encounter Short description Healthcare event during which this observation is made Alternate names Context Definition The healthcare event (e.g. a patient and healthcare provider interaction) during which this observation is made. Requirements For some observations it may be important to know the link between an observation and a particular encounter. Comments This will typically be the encounter the event occurred within, but some events may be initiated prior to or after the official completion of an encounter but still be tied to the context of the encounter (e.g. pre-admission laboratory tests). Data Type Reference(UK Core Encounter) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) workflow:Event.context w5:FiveWs.context v2:PV1 rim:inboundRelationship[typeCode=COMP].source[classCode=ENC, moodCode=EVN]
reference	Σ I	0..1	string	There are no (further) constraints on this element Element Id Observation.encounter.reference Short description Literal reference, Relative, internal or absolute URL Definition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Comments Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
type	Σ	0..1	uriBinding	There are no (further) constraints on this element Element Id Observation.encounter.type Short description Type the reference refers to (e.g. "Patient") Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). Comments This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Data Type uri Binding Aa resource (or, for logical models, the URI of the logical model). ResourceType (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
identifier	Σ	0..1	Identifier	There are no (further) constraints on this element Element Id Observation.encounter.identifier Short description Logical reference, when literal reference is not known Definition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. Comments When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation\|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). Data Type Identifier Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CX / EI (occasionally, more often EI maps to a resource id or a URL) rim:II - The Identifier class is a little looser than the v3 type II because it allows URIs as well as registered OIDs or GUIDs. Also maps to Role[classCode=IDENT] servd:Identifier rim:.identifier
use	Σ ?!	0..1	codeBinding	There are no (further) constraints on this element Element Id Observation.encounter.identifier.use Short description usual \| official \| temp \| secondary \| old (If known) Definition The purpose of this identifier. Requirements Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Comments Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Data Type code Binding Identifies the purpose for this identifier, if known . IdentifierUse (required) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:N/A rim:Role.code or implied by context
type	Σ	0..1	CodeableConceptBinding	There are no (further) constraints on this element Element Id Observation.encounter.identifier.type Short description Description of identifier Definition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Requirements Allows users to make use of identifiers when the identifier system is not known. Comments This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. Data Type CodeableConcept Binding A coded type for an identifier that can be used to determine which identifier to use for a specific purpose. Identifier Type Codes (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD v2:CX.5 rim:Role.code or implied by context
system	Σ	0..1	uri	There are no (further) constraints on this element Element Id Observation.encounter.identifier.system Short description The namespace for the identifier value Definition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. Requirements There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Comments Identifier.system is always case sensitive. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General http://www.acme.com/identifiers/patient Mappings rim:n/a v2:CX.4 / EI-2-4 rim:II.root or Role.id.root servd:./IdentifierType
value	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.encounter.identifier.value Short description The value that is unique Definition The portion of the identifier typically relevant to the user and which is unique within the context of the system. Comments If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General 123456 Mappings rim:n/a v2:CX.1 / EI.1 rim:II.extension or II.root if system indicates OID or GUID (Or Role.id.extension or root) servd:./Value
period	Σ I	0..1	Period	There are no (further) constraints on this element Element Id Observation.encounter.identifier.period Short description Time period when id is/was valid for use Definition Time period during which identifier is/was valid for use. Comments A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. Data Type Period Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` per-1:If present, start SHALL have a lower value than end `start.hasValue().not() or end.hasValue().not() or (start <= end)` Mappings rim:n/a v2:DR rim:IVL<TS>[lowClosed="true" and highClosed="true"] or URG<TS>[lowClosed="true" and highClosed="true"] v2:CX.7 + CX.8 rim:Role.effectiveTime or implied by context servd:./StartDate and ./EndDate
assigner	Σ I	0..1	Reference(UK Core Organization)	There are no (further) constraints on this element Element Id Observation.encounter.identifier.assigner Short description Organization that issued id (may be just text) Definition Organization that issued/manages the identifier. Comments The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Data Type Reference(UK Core Organization) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) v2:CX.4 / (CX.4,CX.9,CX.10) rim:II.assigningAuthorityName but note that this is an improper use by the definition of the field. Also Role.scoper servd:./IdentifierIssuingAuthority
display	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.encounter.display Short description Text alternative for the resource Definition Plain text narrative that identifies the resource in addition to the resource reference. Comments This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
effective[x]	S Σ	1..1		Element Id Observation.effective[x] Short description Clinically relevant time/time-period for observation Alternate names Occurrence Definition The date and time the result was asserted. `"effectiveDateTime": "2020-09-23T13:00:08.476+00:00"` Requirements Knowing when an observation was deemed true is important to its relevance as well as determining trends. Comments At least a date should be present unless this observation is a historical report. For recording imprecise or "fuzzy" times (For example, a blood glucose measurement taken "after breakfast") use the Timing datatype which allow the measurement to be tied to regular life events. Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a workflow:Event.occurrence[x] w5:FiveWs.done[x] v2:OBX-14, and/or OBX-19 after v2.4 (depends on who observation made) rim:effectiveTime
effectiveDateTime			dateTime	Data Type dateTime
issued	Σ	0..1	instant	There are no (further) constraints on this element Element Id Observation.issued Short description Date/Time this version was made available Definition The date and time this version of the observation was made available to providers, typically after the results have been reviewed and verified. Comments For Observations that don’t require review and verification, it may be the same as the `lastUpdated` time of the resource itself. For Observations that do require review and verification for certain updates, it might not be the same as the `lastUpdated` time of the resource itself due to a non-clinically significant update that doesn’t require the new version to be reviewed and verified again. Data Type instant Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a w5:FiveWs.recorded v2:OBR.22 (or MSH.7), or perhaps OBX-19 (depends on who observation made) rim:participation[typeCode=AUT].time
performer	S Σ I	0..*	NHSDigitalReference(NHSDigitalOrganization \| UK Core CareTeam \| NHSDigitalPatient \| NHSDigitalPractitionerRoleMinimal)	Element Id Observation.performer Short description A reference from one resource to another Definition Who was responsible for asserting the observed value as "true". `"performer": [ { "type": "Organization", "identifier": { "type": { "coding": [ { "system": "https://fhir.nhs.uk/CodeSystem/organisation-role", "code": "173", "display": "PATHOLOGY LAB" } ] }, "value": "LFD004" } }, { "type": "Organization", "identifier": { "type": { "coding": [ { "system": "https://fhir.nhs.uk/Id/OrgType", "code": "TestCentreId", "display": "Testing Centre" } ] }, "value": "WKE03" } } ]` Requirements May give a degree of confidence in the observation and also indicates where follow-up questions should be directed. Comments References SHALL be a reference to an actual FHIR resource, and SHALL be resolveable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository. Data Type NHSDigitalReference(NHSDigitalOrganization \| UK Core CareTeam \| NHSDigitalPatient \| NHSDigitalPractitionerRoleMinimal) Allowed aggregation: referenced Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` performer:An identifier reference or resource reference must be provided `(reference.exists() or identifier.exists())` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) workflow:Event.performer.actor w5:FiveWs.actor v2:OBX.15 / (Practitioner) OBX-16, PRT-5:PRT-4='RO' / (Device) OBX-18 , PRT-10:PRT-4='EQUIP' / (Organization) OBX-23, PRT-8:PRT-4='PO' rim:participation[typeCode=PRF]
reference	Σ I	0..1	string	There are no (further) constraints on this element Element Id Observation.performer.reference Short description Literal reference, Relative, internal or absolute URL Definition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Comments Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
type	Σ	0..1	uriBinding	There are no (further) constraints on this element Element Id Observation.performer.type Short description Type the reference refers to (e.g. "Patient") Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). Comments This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Data Type uri Binding Aa resource (or, for logical models, the URI of the logical model). ResourceType (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
identifier	Σ	0..1	Identifier	There are no (further) constraints on this element Element Id Observation.performer.identifier Short description Logical reference, when literal reference is not known Definition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. Comments When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation\|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). Data Type Identifier Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CX / EI (occasionally, more often EI maps to a resource id or a URL) rim:II - The Identifier class is a little looser than the v3 type II because it allows URIs as well as registered OIDs or GUIDs. Also maps to Role[classCode=IDENT] servd:Identifier rim:.identifier
use	Σ ?!	0..1	codeBinding	There are no (further) constraints on this element Element Id Observation.performer.identifier.use Short description usual \| official \| temp \| secondary \| old (If known) Definition The purpose of this identifier. Requirements Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Comments Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Data Type code Binding Identifies the purpose for this identifier, if known . IdentifierUse (required) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:N/A rim:Role.code or implied by context
type	Σ	0..1	CodeableConceptBinding	There are no (further) constraints on this element Element Id Observation.performer.identifier.type Short description Description of identifier Definition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Requirements Allows users to make use of identifiers when the identifier system is not known. Comments This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. Data Type CodeableConcept Binding A coded type for an identifier that can be used to determine which identifier to use for a specific purpose. Identifier Type Codes (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD v2:CX.5 rim:Role.code or implied by context
system	Σ	0..1	uri	There are no (further) constraints on this element Element Id Observation.performer.identifier.system Short description The namespace for the identifier value Definition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. Requirements There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Comments Identifier.system is always case sensitive. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General http://www.acme.com/identifiers/patient Mappings rim:n/a v2:CX.4 / EI-2-4 rim:II.root or Role.id.root servd:./IdentifierType
value	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.performer.identifier.value Short description The value that is unique Definition The portion of the identifier typically relevant to the user and which is unique within the context of the system. Comments If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General 123456 Mappings rim:n/a v2:CX.1 / EI.1 rim:II.extension or II.root if system indicates OID or GUID (Or Role.id.extension or root) servd:./Value
period	Σ I	0..1	Period	There are no (further) constraints on this element Element Id Observation.performer.identifier.period Short description Time period when id is/was valid for use Definition Time period during which identifier is/was valid for use. Comments A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. Data Type Period Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` per-1:If present, start SHALL have a lower value than end `start.hasValue().not() or end.hasValue().not() or (start <= end)` Mappings rim:n/a v2:DR rim:IVL<TS>[lowClosed="true" and highClosed="true"] or URG<TS>[lowClosed="true" and highClosed="true"] v2:CX.7 + CX.8 rim:Role.effectiveTime or implied by context servd:./StartDate and ./EndDate
assigner	Σ I	0..1	Reference(UK Core Organization)	There are no (further) constraints on this element Element Id Observation.performer.identifier.assigner Short description Organization that issued id (may be just text) Definition Organization that issued/manages the identifier. Comments The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Data Type Reference(UK Core Organization) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) v2:CX.4 / (CX.4,CX.9,CX.10) rim:II.assigningAuthorityName but note that this is an improper use by the definition of the field. Also Role.scoper servd:./IdentifierIssuingAuthority
display	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.performer.display Short description Text alternative for the resource Definition Plain text narrative that identifies the resource in addition to the resource reference. Comments This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
value[x]	S Σ I	0..1		Element Id Observation.value[x] Short description Actual result Definition COVID-19 valueCodeableConcept The COVID 19 test result. This is a SNOMED CT from the valueSet associated with the `code`, see Observation Definition `"valueCodeableConcept": { "coding": [ { "system": "http://snomed.info/sct", "code": "1240581000000104", "display": "SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) detection result positive" } ], "text": "SARS-CoV-2-ORGY" },` Requirements An observation exists to have a value, though it might not if it is in error, or if it represents a group of observations. Comments An observation may have; 1) a single value here, 2) both a value and a set of related or component values, or 3) only a set of related or component values. If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the Notes section below. Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a sct-concept:< 441742003 \|Evaluation finding\| v2:OBX.2, OBX.5, OBX.6 rim:value sct-attr:363714003 \|Interprets\|
valueQuantity			Quantity	There are no (further) constraints on this element Data Type Quantity
valueCodeableConcept			CodeableConcept	There are no (further) constraints on this element Data Type CodeableConcept
valueString			string	There are no (further) constraints on this element Data Type string
valueBoolean			boolean	There are no (further) constraints on this element Data Type boolean
valueInteger			integer	There are no (further) constraints on this element Data Type integer
valueRange			Range	There are no (further) constraints on this element Data Type Range
valueRatio			Ratio	There are no (further) constraints on this element Data Type Ratio
valueSampledData			SampledData	There are no (further) constraints on this element Data Type SampledData
valueTime			time	There are no (further) constraints on this element Data Type time
valueDateTime			dateTime	There are no (further) constraints on this element Data Type dateTime
valuePeriod			Period	There are no (further) constraints on this element Data Type Period
dataAbsentReason	I	0..1	CodeableConceptBinding	There are no (further) constraints on this element Element Id Observation.dataAbsentReason Short description Why the result is missing Definition Provides a reason why the expected value in the element Observation.value[x] is missing. Requirements For many results it is necessary to handle exceptional values in measurements. Comments Null or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "specimen unsatisfactory". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Note that an observation may only be reported if there are values to report. For example differential cell counts values may be reported only when > 0. Because of these options, use-case agreements are required to interpret general observations for null or exceptional values. Data Type CodeableConcept Binding Codes specifying why the result (`Observation.value[x]`) is missing. DataAbsentReason (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD v2:N/A rim:value.nullFlavor
interpretation		0..*	CodeableConceptBinding	There are no (further) constraints on this element Element Id Observation.interpretation Short description High, low, normal, etc. Alternate names Abnormal Flag Definition A categorical assessment of an observation value. For example, high, low, normal. Requirements For some results, particularly numeric results, an interpretation is necessary to fully understand the significance of a result. Comments Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. Data Type CodeableConcept Binding Codes identifying interpretations of observations. ObservationInterpretationCodes (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD sct-concept:< 260245000 \|Findings values\| v2:OBX-8 rim:interpretationCode sct-attr:363713009 \|Has interpretation\|
note		0..*	Annotation	There are no (further) constraints on this element Element Id Observation.note Short description Comments about the observation Definition Comments about the observation or the results. Requirements Need to be able to provide free text additional information. Comments May include general statements about the observation, or statements about significant, unexpected or unreliable results values, or information about its source when relevant to its interpretation. Data Type Annotation Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:N/A rim:Act v2:NTE.3 (partner NTE to OBX, or sometimes another (child?) OBX) rim:subjectOf.observationEvent[code="annotation"].value
author[x]	Σ	0..1		There are no (further) constraints on this element Element Id Observation.note.author[x] Short description Individual responsible for the annotation Definition The individual responsible for making the annotation. Comments Organization is used when there's no need for specific attribution as to who made the comment. Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:N/A rim:Act.participant[typeCode=AUT].role
authorString			string	There are no (further) constraints on this element Data Type string
authorReference			Reference(UK Core Organization \| UK Core Patient \| UK Core Practitioner \| UK Core RelatedPerson)	There are no (further) constraints on this element Data Type Reference(UK Core Organization \| UK Core Patient \| UK Core Practitioner \| UK Core RelatedPerson)
time	Σ	0..1	dateTime	There are no (further) constraints on this element Element Id Observation.note.time Short description When the annotation was made Definition Indicates when this particular annotation was made. Data Type dateTime Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:N/A rim:Act.effectiveTime
text	Σ	1..1	markdown	There are no (further) constraints on this element Element Id Observation.note.text Short description The annotation - text content (as markdown) Definition The text of the annotation in markdown format. Comments Systems are not required to have markdown support, so the text should be readable without markdown processing. The markdown syntax is GFM - see https://github.github.com/gfm/ Data Type markdown Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:N/A rim:Act.text
bodySite		0..1	CodeableConcept	There are no (further) constraints on this element Element Id Observation.bodySite Short description Observed body part Definition Indicates the site on the subject's body where the observation was made (i.e. the target site). Comments Only used if not implicit in code found in Observation.code. In many systems, this may be represented as a related observation instead of an inline component. If the use case requires BodySite to be handled as a separate resource (e.g. to identify and track separately) then use the standard extension bodySite. Data Type CodeableConcept Binding Codes describing anatomical locations. May include laterality. SNOMEDCTBodyStructures (example) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD sct-concept:< 123037004 \|Body structure\| v2:OBX-20 rim:targetSiteCode sct-attr:718497002 \|Inherent location\|
coding	Σ	0..*	Coding	There are no (further) constraints on this element Element Id Observation.bodySite.coding Short description Code defined by a terminology system Definition A reference to a code defined by a terminology system. Requirements Allows for alternative encodings within a code system, and translations to other code systems. Comments Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. Data Type Coding Sliced: Unordered, Open, by code(Value), system(Value) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE subset one of the sets of component 1-3 or 4-6 rim:CV orim:fhir:Coding rdfs:subClassOf dt:CDCoding v2:CE.1-8, CE.10-22 rim:union(., ./translation) orim:fhir:CodeableConcept.coding rdfs:subPropertyOf dt:CD.coding
snomedCT	Σ	0..1	CodingBinding	There are no (further) constraints on this element Element Id Observation.bodySite.coding:snomedCT Short description Code defined by a terminology system Definition A reference to a code defined by a terminology system. Requirements Allows for alternative encodings within a code system, and translations to other code systems. Comments Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. Data Type Coding Binding A code from the SNOMED Clinical Terminology UK with the expression (<<442083009 \|anatomical or acquired body structure\|) UKCoreBodySite (preferred) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE subset one of the sets of component 1-3 or 4-6 rim:CV orim:fhir:Coding rdfs:subClassOf dt:CDCoding v2:CE.1-8, CE.10-22 rim:union(., ./translation) orim:fhir:CodeableConcept.coding rdfs:subPropertyOf dt:CD.coding
system	Σ	1..1	uriFixed Value	There are no (further) constraints on this element Element Id Observation.bodySite.coding:snomedCT.system Short description Identity of the terminology system Definition The identification of the code system that defines the meaning of the symbol in the code. Requirements Need to be unambiguous about the source of the definition of the symbol. Comments The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Fixed Value http://snomed.info/sct Mappings rim:n/a v2:CE.3 rim:./codeSystem orim:*fhir:Coding.system rdfs:subPropertyOf dt:CDCoding.codeSystem
version	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.bodySite.coding:snomedCT.version Short description Version of the system - if relevant Definition The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. Comments Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.7 rim:./codeSystemVersion orim:*fhir:Coding.version rdfs:subPropertyOf dt:CDCoding.codeSystemVersion
code	Σ	1..1	code	There are no (further) constraints on this element Element Id Observation.bodySite.coding:snomedCT.code Short description Symbol in syntax defined by the system Definition A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). Requirements Need to refer to a particular code in the system. Comments Note that FHIR strings SHALL NOT exceed 1MB in size Data Type code Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.1 rim:./code orim:*fhir:Coding.code rdfs:subPropertyOf dt:CDCoding.code
display	Σ	1..1	string	There are no (further) constraints on this element Element Id Observation.bodySite.coding:snomedCT.display Short description Representation defined by the system Definition A representation of the meaning of the code in the system, following the rules of the system. Requirements Need to be able to carry a human-readable meaning of the code for readers that do not know the system. Comments Note that FHIR strings SHALL NOT exceed 1MB in size Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.2 - but note this is not well followed rim:CV.displayName orim:*fhir:Coding.display rdfs:subPropertyOf dt:CDCoding.displayName
userSelected	Σ	0..1	boolean	There are no (further) constraints on this element Element Id Observation.bodySite.coding:snomedCT.userSelected Short description If this coding was chosen directly by the user Definition Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). Requirements This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing. Comments Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. Data Type boolean Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:Sometimes implied by being first rim:CD.codingRationale orim:fhir:Coding.userSelected fhir:mapsTo dt:CDCoding.codingRationale. fhir:Coding.userSelected fhir:hasMap fhir:Coding.userSelected.map. fhir:Coding.userSelected.map a fhir:Map; fhir:target dt:CDCoding.codingRationale. fhir:Coding.userSelected\#true a [ fhir:source "true"; fhir:target dt:CDCoding.codingRationale\#O ]
text	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.bodySite.text Short description Plain text representation of the concept Definition A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. Requirements The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source. Comments Very often the text is the same as a displayName of one of the codings. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.9. But note many systems use CE.2 for this rim:./originalText[mediaType/code="text/plain"]/data orim:fhir:CodeableConcept.text rdfs:subPropertyOf dt:CD.originalText
method	S	0..1	CodeableConceptBinding	Element Id Observation.method Short description How it was done Definition The name of the test that was performed, this is a SNOMED CT concept. `"method": { "coding": [ { "system": "http://snomed.info/sct", "code": "1240461000000109", "display": "Measurement of SARS-CoV-2 antibody (procedure)" } ] },` Requirements In some cases, method can impact results and is thus used for determining whether results can be compared or determining significance of results. Comments Only used if not implicit in code for Observation.code. Data Type CodeableConcept Binding Methods for simple observations. ObservationMethods (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD v2:OBX-17 rim:methodCode
coding	Σ	0..*	Coding	There are no (further) constraints on this element Element Id Observation.method.coding Short description Code defined by a terminology system Definition A reference to a code defined by a terminology system. Requirements Allows for alternative encodings within a code system, and translations to other code systems. Comments Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. Data Type Coding Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE subset one of the sets of component 1-3 or 4-6 rim:CV orim:fhir:Coding rdfs:subClassOf dt:CDCoding v2:CE.1-8, CE.10-22 rim:union(., ./translation) orim:fhir:CodeableConcept.coding rdfs:subPropertyOf dt:CD.coding
system	Σ	1..1	uri	There are no (further) constraints on this element Element Id Observation.method.coding.system Short description Identity of the terminology system Definition The identification of the code system that defines the meaning of the symbol in the code. Requirements Need to be unambiguous about the source of the definition of the symbol. Comments The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.3 rim:./codeSystem orim:*fhir:Coding.system rdfs:subPropertyOf dt:CDCoding.codeSystem
version	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.method.coding.version Short description Version of the system - if relevant Definition The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. Comments Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.7 rim:./codeSystemVersion orim:*fhir:Coding.version rdfs:subPropertyOf dt:CDCoding.codeSystemVersion
code	Σ	1..1	code	There are no (further) constraints on this element Element Id Observation.method.coding.code Short description Symbol in syntax defined by the system Definition A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). Requirements Need to refer to a particular code in the system. Comments Note that FHIR strings SHALL NOT exceed 1MB in size Data Type code Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.1 rim:./code orim:*fhir:Coding.code rdfs:subPropertyOf dt:CDCoding.code
display	Σ	1..1	string	There are no (further) constraints on this element Element Id Observation.method.coding.display Short description Representation defined by the system Definition A representation of the meaning of the code in the system, following the rules of the system. Requirements Need to be able to carry a human-readable meaning of the code for readers that do not know the system. Comments Note that FHIR strings SHALL NOT exceed 1MB in size Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.2 - but note this is not well followed rim:CV.displayName orim:*fhir:Coding.display rdfs:subPropertyOf dt:CDCoding.displayName
userSelected	Σ	0..1	boolean	There are no (further) constraints on this element Element Id Observation.method.coding.userSelected Short description If this coding was chosen directly by the user Definition Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). Requirements This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing. Comments Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. Data Type boolean Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:Sometimes implied by being first rim:CD.codingRationale orim:fhir:Coding.userSelected fhir:mapsTo dt:CDCoding.codingRationale. fhir:Coding.userSelected fhir:hasMap fhir:Coding.userSelected.map. fhir:Coding.userSelected.map a fhir:Map; fhir:target dt:CDCoding.codingRationale. fhir:Coding.userSelected\#true a [ fhir:source "true"; fhir:target dt:CDCoding.codingRationale\#O ]
text	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.method.text Short description Plain text representation of the concept Definition A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. Requirements The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source. Comments Very often the text is the same as a displayName of one of the codings. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.9. But note many systems use CE.2 for this rim:./originalText[mediaType/code="text/plain"]/data orim:fhir:CodeableConcept.text rdfs:subPropertyOf dt:CD.originalText
specimen	S I	0..1	Reference(UK Core Specimen)	Element Id Observation.specimen Short description Specimen used for this observation Definition For COVID-19 Test History. The identifier of the specimen used for the test. `"specimen": { "identifier": { "system": "https://fhir.nhs.uk/Id/SpecimenId", "value": "eb89a392-5b20-11eb-ae93-0242ac130002" } },` Comments Should only be used if not implicit in code found in `Observation.code`. Observations are not made on specimens themselves; they are made on a subject, but in many cases by the means of a specimen. Note that although specimens are often involved, they are not always tracked and reported explicitly. Also note that observation resources may be used in contexts that track the specimen explicitly (e.g. Diagnostic Report). Data Type Reference(UK Core Specimen) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) sct-concept:< 123038009 \|Specimen\| v2:SPM segment rim:participation[typeCode=SPC].specimen sct-attr:704319004 \|Inherent in\|
reference	Σ I	0..1	string	There are no (further) constraints on this element Element Id Observation.specimen.reference Short description Literal reference, Relative, internal or absolute URL Definition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Comments Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
type	Σ	0..1	uriBinding	There are no (further) constraints on this element Element Id Observation.specimen.type Short description Type the reference refers to (e.g. "Patient") Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). Comments This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Data Type uri Binding Aa resource (or, for logical models, the URI of the logical model). ResourceType (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
identifier	Σ	0..1	Identifier	There are no (further) constraints on this element Element Id Observation.specimen.identifier Short description Logical reference, when literal reference is not known Definition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. Comments When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation\|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). Data Type Identifier Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CX / EI (occasionally, more often EI maps to a resource id or a URL) rim:II - The Identifier class is a little looser than the v3 type II because it allows URIs as well as registered OIDs or GUIDs. Also maps to Role[classCode=IDENT] servd:Identifier rim:.identifier
use	Σ ?!	0..1	codeBinding	There are no (further) constraints on this element Element Id Observation.specimen.identifier.use Short description usual \| official \| temp \| secondary \| old (If known) Definition The purpose of this identifier. Requirements Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Comments Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Data Type code Binding Identifies the purpose for this identifier, if known . IdentifierUse (required) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:N/A rim:Role.code or implied by context
type	Σ	0..1	CodeableConceptBinding	There are no (further) constraints on this element Element Id Observation.specimen.identifier.type Short description Description of identifier Definition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Requirements Allows users to make use of identifiers when the identifier system is not known. Comments This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. Data Type CodeableConcept Binding A coded type for an identifier that can be used to determine which identifier to use for a specific purpose. Identifier Type Codes (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD v2:CX.5 rim:Role.code or implied by context
system	Σ	1..1	uri	There are no (further) constraints on this element Element Id Observation.specimen.identifier.system Short description The namespace for the identifier value Definition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. Requirements There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Comments Identifier.system is always case sensitive. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General http://www.acme.com/identifiers/patient Mappings rim:n/a v2:CX.4 / EI-2-4 rim:II.root or Role.id.root servd:./IdentifierType
value	Σ	1..1	string	There are no (further) constraints on this element Element Id Observation.specimen.identifier.value Short description The value that is unique Definition The portion of the identifier typically relevant to the user and which is unique within the context of the system. Comments If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General 123456 Mappings rim:n/a v2:CX.1 / EI.1 rim:II.extension or II.root if system indicates OID or GUID (Or Role.id.extension or root) servd:./Value
period	Σ I	0..1	Period	There are no (further) constraints on this element Element Id Observation.specimen.identifier.period Short description Time period when id is/was valid for use Definition Time period during which identifier is/was valid for use. Comments A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. Data Type Period Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` per-1:If present, start SHALL have a lower value than end `start.hasValue().not() or end.hasValue().not() or (start <= end)` Mappings rim:n/a v2:DR rim:IVL<TS>[lowClosed="true" and highClosed="true"] or URG<TS>[lowClosed="true" and highClosed="true"] v2:CX.7 + CX.8 rim:Role.effectiveTime or implied by context servd:./StartDate and ./EndDate
assigner	Σ I	0..1	Reference(UK Core Organization)	There are no (further) constraints on this element Element Id Observation.specimen.identifier.assigner Short description Organization that issued id (may be just text) Definition Organization that issued/manages the identifier. Comments The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Data Type Reference(UK Core Organization) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) v2:CX.4 / (CX.4,CX.9,CX.10) rim:II.assigningAuthorityName but note that this is an improper use by the definition of the field. Also Role.scoper servd:./IdentifierIssuingAuthority
display	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.specimen.display Short description Text alternative for the resource Definition Plain text narrative that identifies the resource in addition to the resource reference. Comments This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
device	S I	0..1	Reference(DeviceMetric \| UK Core Device)	Element Id Observation.device Short description (Measurement) Device Definition Details of the COVID-19 test kit used. `"device": { "identifier": { "system": "https://fhir.nhs.uk/Id/Covid19-TestKit", "value": "LFT" }, "display": "Lateral Flow Test" }` Comments Note that this is not meant to represent a device involved in the transmission of the result, e.g., a gateway. Such devices may be documented using the Provenance resource where relevant. Data Type Reference(DeviceMetric \| UK Core Device) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) sct-concept:< 49062001 \|Device\| v2:OBX-17 / PRT -10 rim:participation[typeCode=DEV] sct-attr:424226004 \|Using device\|
reference	Σ I	0..1	string	There are no (further) constraints on this element Element Id Observation.device.reference Short description Literal reference, Relative, internal or absolute URL Definition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Comments Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
type	Σ	0..1	uriBinding	There are no (further) constraints on this element Element Id Observation.device.type Short description Type the reference refers to (e.g. "Patient") Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). Comments This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Data Type uri Binding Aa resource (or, for logical models, the URI of the logical model). ResourceType (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
identifier	Σ	0..1	Identifier	There are no (further) constraints on this element Element Id Observation.device.identifier Short description Logical reference, when literal reference is not known Definition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. Comments When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation\|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). Data Type Identifier Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CX / EI (occasionally, more often EI maps to a resource id or a URL) rim:II - The Identifier class is a little looser than the v3 type II because it allows URIs as well as registered OIDs or GUIDs. Also maps to Role[classCode=IDENT] servd:Identifier rim:.identifier
use	Σ ?!	0..1	codeBinding	There are no (further) constraints on this element Element Id Observation.device.identifier.use Short description usual \| official \| temp \| secondary \| old (If known) Definition The purpose of this identifier. Requirements Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Comments Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Data Type code Binding Identifies the purpose for this identifier, if known . IdentifierUse (required) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:N/A rim:Role.code or implied by context
type	Σ	0..1	CodeableConceptBinding	There are no (further) constraints on this element Element Id Observation.device.identifier.type Short description Description of identifier Definition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Requirements Allows users to make use of identifiers when the identifier system is not known. Comments This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. Data Type CodeableConcept Binding A coded type for an identifier that can be used to determine which identifier to use for a specific purpose. Identifier Type Codes (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD v2:CX.5 rim:Role.code or implied by context
system	Σ	1..1	uri	There are no (further) constraints on this element Element Id Observation.device.identifier.system Short description The namespace for the identifier value Definition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. Requirements There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Comments Identifier.system is always case sensitive. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General http://www.acme.com/identifiers/patient Mappings rim:n/a v2:CX.4 / EI-2-4 rim:II.root or Role.id.root servd:./IdentifierType
value	Σ	1..1	string	There are no (further) constraints on this element Element Id Observation.device.identifier.value Short description The value that is unique Definition The portion of the identifier typically relevant to the user and which is unique within the context of the system. Comments If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General 123456 Mappings rim:n/a v2:CX.1 / EI.1 rim:II.extension or II.root if system indicates OID or GUID (Or Role.id.extension or root) servd:./Value
period	Σ I	0..1	Period	There are no (further) constraints on this element Element Id Observation.device.identifier.period Short description Time period when id is/was valid for use Definition Time period during which identifier is/was valid for use. Comments A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. Data Type Period Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` per-1:If present, start SHALL have a lower value than end `start.hasValue().not() or end.hasValue().not() or (start <= end)` Mappings rim:n/a v2:DR rim:IVL<TS>[lowClosed="true" and highClosed="true"] or URG<TS>[lowClosed="true" and highClosed="true"] v2:CX.7 + CX.8 rim:Role.effectiveTime or implied by context servd:./StartDate and ./EndDate
assigner	Σ I	0..1	Reference(UK Core Organization)	There are no (further) constraints on this element Element Id Observation.device.identifier.assigner Short description Organization that issued id (may be just text) Definition Organization that issued/manages the identifier. Comments The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Data Type Reference(UK Core Organization) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) v2:CX.4 / (CX.4,CX.9,CX.10) rim:II.assigningAuthorityName but note that this is an improper use by the definition of the field. Also Role.scoper servd:./IdentifierIssuingAuthority
display	Σ	1..1	string	There are no (further) constraints on this element Element Id Observation.device.display Short description Text alternative for the resource Definition Plain text narrative that identifies the resource in addition to the resource reference. Comments This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
referenceRange	I	0..*	BackboneElement	There are no (further) constraints on this element Element Id Observation.referenceRange Short description Provides guide for interpretation Definition Guidance on how to interpret the value by comparison to a normal or recommended range. Multiple reference ranges are interpreted as an "OR". In other words, to represent two distinct target populations, two `referenceRange` elements would be used. Requirements Knowing what values are considered "normal" can help evaluate the significance of a particular result. Need to be able to provide multiple reference ranges for different contexts. Comments Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. Data Type BackboneElement Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` obs-3:Must have at least a low or a high or text `low.exists() or high.exists() or text.exists()` Mappings rim:n/a v2:OBX.7 rim:outboundRelationship[typeCode=REFV]/target[classCode=OBS, moodCode=EVN]
low	I	0..1	SimpleQuantity	There are no (further) constraints on this element Element Id Observation.referenceRange.low Short description Low Range, if relevant Definition The value of the low bound of the reference range. The low bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the low bound is omitted, it is assumed to be meaningless (e.g. reference range is <=2.3). Comments The context of use may frequently define what kind of quantity this is and therefore what kind of units can be used. The context of use may also restrict the values for the comparator. Data Type SimpleQuantity Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` qty-3:If a code for the unit is present, the system SHALL also be present `code.empty() or system.exists()` sqty-1:The comparator is not used on a SimpleQuantity `comparator.empty()` Mappings rim:n/a v2:SN (see also Range) or CQ rim:PQ, IVL<PQ>, MO, CO, depending on the values v2:OBX-7 rim:value:IVL_PQ.low
high	I	0..1	SimpleQuantity	There are no (further) constraints on this element Element Id Observation.referenceRange.high Short description High Range, if relevant Definition The value of the high bound of the reference range. The high bound of the reference range endpoint is inclusive of the value (e.g. reference range is >=5 - <=9). If the high bound is omitted, it is assumed to be meaningless (e.g. reference range is >= 2.3). Comments The context of use may frequently define what kind of quantity this is and therefore what kind of units can be used. The context of use may also restrict the values for the comparator. Data Type SimpleQuantity Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` qty-3:If a code for the unit is present, the system SHALL also be present `code.empty() or system.exists()` sqty-1:The comparator is not used on a SimpleQuantity `comparator.empty()` Mappings rim:n/a v2:SN (see also Range) or CQ rim:PQ, IVL<PQ>, MO, CO, depending on the values v2:OBX-7 rim:value:IVL_PQ.high
type		0..1	CodeableConceptBinding	There are no (further) constraints on this element Element Id Observation.referenceRange.type Short description Reference range qualifier Definition Codes to indicate the what part of the targeted reference population it applies to. For example, the normal or therapeutic range. Requirements Need to be able to say what kind of reference range this is - normal, recommended, therapeutic, etc., - for proper interpretation. Comments This SHOULD be populated if there is more than one range. If this element is not present then the normal range is assumed. Data Type CodeableConcept Binding Code for the meaning of a reference range. ObservationReferenceRangeMeaningCodes (preferred) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD sct-concept:< 260245000 \|Findings values\| OR < 365860008 \|General clinical state finding\| OR < 250171008 \|Clinical history or observation findings\| OR < 415229000 \|Racial group\| OR < 365400002 \|Finding of puberty stage\| OR < 443938003 \|Procedure carried out on subject\| v2:OBX-10 rim:interpretationCode
appliesTo		0..*	CodeableConcept	There are no (further) constraints on this element Element Id Observation.referenceRange.appliesTo Short description Reference range population Definition Codes to indicate the target population this reference range applies to. For example, a reference range may be based on the normal population or a particular sex or race. Multiple `appliesTo` are interpreted as an "AND" of the target populations. For example, to represent a target population of African American females, both a code of female and a code for African American would be used. Requirements Need to be able to identify the target population for proper interpretation. Comments This SHOULD be populated if there is more than one range. If this element is not present then the normal population is assumed. Data Type CodeableConcept Binding Codes identifying the population the reference range applies to. ObservationReferenceRangeAppliesToCodes (example) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD sct-concept:< 260245000 \|Findings values\| OR < 365860008 \|General clinical state finding\| OR < 250171008 \|Clinical history or observation findings\| OR < 415229000 \|Racial group\| OR < 365400002 \|Finding of puberty stage\| OR < 443938003 \|Procedure carried out on subject\| v2:OBX-10 rim:interpretationCode
age	I	0..1	Range	There are no (further) constraints on this element Element Id Observation.referenceRange.age Short description Applicable age range, if relevant Definition The age at which this reference range is applicable. This is a neonatal age (e.g. number of weeks at term) if the meaning says so. Requirements Some analytes vary greatly over age. Comments The stated low and high value are assumed to have arbitrarily high precision when it comes to determining which values are in the range. I.e. 1.99 is not in the range 2 -> 3. Data Type Range Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` rng-2:If present, low SHALL have a lower value than high `low.empty() or high.empty() or (low <= high)` Mappings rim:n/a v2:NR and also possibly SN (but see also quantity) rim:IVL<QTY[not(type="TS")]> [lowClosed="true" and highClosed="true"]or URG<QTY[not(type="TS")]> rim:outboundRelationship[typeCode=PRCN].targetObservationCriterion[code="age"].value
text		0..1	string	There are no (further) constraints on this element Element Id Observation.referenceRange.text Short description Text based reference range in an observation Definition Text based reference range in an observation which may be used when a quantitative range is not appropriate for an observation. An example would be a reference value of "Negative" or a list or table of "normals". Comments Note that FHIR strings SHALL NOT exceed 1MB in size Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:OBX-7 rim:value:ST
hasMember	Σ I	0..*	Reference(MolecularSequence \| UK Core Observation \| UK Core QuestionnaireResponse)	There are no (further) constraints on this element Element Id Observation.hasMember Short description Related resource that belongs to the Observation group Definition This observation is a group observation (e.g. a battery, a panel of tests, a set of vital sign measurements) that includes the target as a member of the group. Comments When using this element, an observation will typically have either a value or a set of related resources, although both may be present in some cases. For a discussion on the ways Observations can assembled in groups together, see Notes below. Note that a system may calculate results from QuestionnaireResponse into a final score and represent the score as an Observation. Data Type Reference(MolecularSequence \| UK Core Observation \| UK Core QuestionnaireResponse) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) v2:Relationships established by OBX-4 usage rim:outBoundRelationship
reference	Σ I	0..1	string	There are no (further) constraints on this element Element Id Observation.hasMember.reference Short description Literal reference, Relative, internal or absolute URL Definition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Comments Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
type	Σ	0..1	uriBinding	There are no (further) constraints on this element Element Id Observation.hasMember.type Short description Type the reference refers to (e.g. "Patient") Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). Comments This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Data Type uri Binding Aa resource (or, for logical models, the URI of the logical model). ResourceType (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
identifier	Σ	0..1	Identifier	There are no (further) constraints on this element Element Id Observation.hasMember.identifier Short description Logical reference, when literal reference is not known Definition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. Comments When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation\|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). Data Type Identifier Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CX / EI (occasionally, more often EI maps to a resource id or a URL) rim:II - The Identifier class is a little looser than the v3 type II because it allows URIs as well as registered OIDs or GUIDs. Also maps to Role[classCode=IDENT] servd:Identifier rim:.identifier
use	Σ ?!	0..1	codeBinding	There are no (further) constraints on this element Element Id Observation.hasMember.identifier.use Short description usual \| official \| temp \| secondary \| old (If known) Definition The purpose of this identifier. Requirements Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Comments Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Data Type code Binding Identifies the purpose for this identifier, if known . IdentifierUse (required) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:N/A rim:Role.code or implied by context
type	Σ	0..1	CodeableConceptBinding	There are no (further) constraints on this element Element Id Observation.hasMember.identifier.type Short description Description of identifier Definition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Requirements Allows users to make use of identifiers when the identifier system is not known. Comments This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. Data Type CodeableConcept Binding A coded type for an identifier that can be used to determine which identifier to use for a specific purpose. Identifier Type Codes (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD v2:CX.5 rim:Role.code or implied by context
system	Σ	0..1	uri	There are no (further) constraints on this element Element Id Observation.hasMember.identifier.system Short description The namespace for the identifier value Definition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. Requirements There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Comments Identifier.system is always case sensitive. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General http://www.acme.com/identifiers/patient Mappings rim:n/a v2:CX.4 / EI-2-4 rim:II.root or Role.id.root servd:./IdentifierType
value	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.hasMember.identifier.value Short description The value that is unique Definition The portion of the identifier typically relevant to the user and which is unique within the context of the system. Comments If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General 123456 Mappings rim:n/a v2:CX.1 / EI.1 rim:II.extension or II.root if system indicates OID or GUID (Or Role.id.extension or root) servd:./Value
period	Σ I	0..1	Period	There are no (further) constraints on this element Element Id Observation.hasMember.identifier.period Short description Time period when id is/was valid for use Definition Time period during which identifier is/was valid for use. Comments A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. Data Type Period Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` per-1:If present, start SHALL have a lower value than end `start.hasValue().not() or end.hasValue().not() or (start <= end)` Mappings rim:n/a v2:DR rim:IVL<TS>[lowClosed="true" and highClosed="true"] or URG<TS>[lowClosed="true" and highClosed="true"] v2:CX.7 + CX.8 rim:Role.effectiveTime or implied by context servd:./StartDate and ./EndDate
assigner	Σ I	0..1	Reference(UK Core Organization)	There are no (further) constraints on this element Element Id Observation.hasMember.identifier.assigner Short description Organization that issued id (may be just text) Definition Organization that issued/manages the identifier. Comments The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Data Type Reference(UK Core Organization) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) v2:CX.4 / (CX.4,CX.9,CX.10) rim:II.assigningAuthorityName but note that this is an improper use by the definition of the field. Also Role.scoper servd:./IdentifierIssuingAuthority
display	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.hasMember.display Short description Text alternative for the resource Definition Plain text narrative that identifies the resource in addition to the resource reference. Comments This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
derivedFrom	Σ I	0..*	Reference(Media \| MolecularSequence \| UK Core DocumentReference \| UK Core Imaging Study \| UK Core Observation \| UK Core QuestionnaireResponse)	There are no (further) constraints on this element Element Id Observation.derivedFrom Short description Related measurements the observation is made from Definition The target resource that represents a measurement from which this observation value is derived. For example, a calculated anion gap or a fetal measurement based on an ultrasound image. Comments All the reference choices that are listed in this element can represent clinical observations and other measurements that may be the source for a derived value. The most common reference will be another Observation. For a discussion on the ways Observations can assembled in groups together, see Notes below. Data Type Reference(Media \| MolecularSequence \| UK Core DocumentReference \| UK Core Imaging Study \| UK Core Observation \| UK Core QuestionnaireResponse) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) v2:Relationships established by OBX-4 usage rim:.targetObservation
reference	Σ I	0..1	string	There are no (further) constraints on this element Element Id Observation.derivedFrom.reference Short description Literal reference, Relative, internal or absolute URL Definition A reference to a location at which the other resource is found. The reference may be a relative reference, in which case it is relative to the service base URL, or an absolute URL that resolves to the location where the resource is found. The reference may be version specific or not. If the reference is not to a FHIR RESTful server, then it should be assumed to be version specific. Internal fragment references (start with '#') refer to contained resources. Comments Using absolute URLs provides a stable scalable approach suitable for a cloud/web context, while using relative/logical references provides a flexible approach suitable for use when trading across closed eco-system boundaries. Absolute URLs do not need to point to a FHIR RESTful server, though this is the preferred approach. If the URL conforms to the structure "/[type]/[id]" then it should be assumed that the reference is to a FHIR RESTful server. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
type	Σ	0..1	uriBinding	There are no (further) constraints on this element Element Id Observation.derivedFrom.type Short description Type the reference refers to (e.g. "Patient") Definition The expected type of the target of the reference. If both Reference.type and Reference.reference are populated and Reference.reference is a FHIR URL, both SHALL be consistent. The type is the Canonical URL of Resource Definition that is the type this reference refers to. References are URLs that are relative to http://hl7.org/fhir/StructureDefinition/ e.g. "Patient" is a reference to http://hl7.org/fhir/StructureDefinition/Patient. Absolute URLs are only allowed for logical models (and can only be used in references in logical models, not resources). Comments This element is used to indicate the type of the target of the reference. This may be used which ever of the other elements are populated (or not). In some cases, the type of the target may be determined by inspection of the reference (e.g. a RESTful URL) or by resolving the target of the reference; if both the type and a reference is provided, the reference SHALL resolve to a resource of the same type as that specified. Data Type uri Binding Aa resource (or, for logical models, the URI of the logical model). ResourceType (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
identifier	Σ	0..1	Identifier	There are no (further) constraints on this element Element Id Observation.derivedFrom.identifier Short description Logical reference, when literal reference is not known Definition An identifier for the target resource. This is used when there is no way to reference the other resource directly, either because the entity it represents is not available through a FHIR server, or because there is no way for the author of the resource to convert a known identifier to an actual location. There is no requirement that a Reference.identifier point to something that is actually exposed as a FHIR instance, but it SHALL point to a business concept that would be expected to be exposed as a FHIR instance, and that instance would need to be of a FHIR resource type allowed by the reference. Comments When an identifier is provided in place of a reference, any system processing the reference will only be able to resolve the identifier to a reference if it understands the business context in which the identifier is used. Sometimes this is global (e.g. a national identifier) but often it is not. For this reason, none of the useful mechanisms described for working with references (e.g. chaining, includes) are possible, nor should servers be expected to be able resolve the reference. Servers may accept an identifier based reference untouched, resolve it, and/or reject it - see CapabilityStatement.rest.resource.referencePolicy. When both an identifier and a literal reference are provided, the literal reference is preferred. Applications processing the resource are allowed - but not required - to check that the identifier matches the literal reference Applications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it. Reference is intended to point to a structure that can potentially be expressed as a FHIR resource, though there is no need for it to exist as an actual FHIR resource instance - except in as much as an application wishes to actual find the target of the reference. The content referred to be the identifier must meet the logical constraints implied by any limitations on what resource types are permitted for the reference. For example, it would not be legitimate to send the identifier for a drug prescription if the type were Reference(Observation\|DiagnosticReport). One of the use-cases for Reference.identifier is the situation where no FHIR representation exists (where the type is Reference (Any). Data Type Identifier Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CX / EI (occasionally, more often EI maps to a resource id or a URL) rim:II - The Identifier class is a little looser than the v3 type II because it allows URIs as well as registered OIDs or GUIDs. Also maps to Role[classCode=IDENT] servd:Identifier rim:.identifier
use	Σ ?!	0..1	codeBinding	There are no (further) constraints on this element Element Id Observation.derivedFrom.identifier.use Short description usual \| official \| temp \| secondary \| old (If known) Definition The purpose of this identifier. Requirements Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers. Comments Applications can assume that an identifier is permanent unless it explicitly says that it is temporary. Data Type code Binding Identifies the purpose for this identifier, if known . IdentifierUse (required) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:N/A rim:Role.code or implied by context
type	Σ	0..1	CodeableConceptBinding	There are no (further) constraints on this element Element Id Observation.derivedFrom.identifier.type Short description Description of identifier Definition A coded type for the identifier that can be used to determine which identifier to use for a specific purpose. Requirements Allows users to make use of identifiers when the identifier system is not known. Comments This element deals only with general categories of identifiers. It SHOULD not be used for codes that correspond 1..1 with the Identifier.system. Some identifiers may fall into multiple categories due to common usage. Where the system is known, a type is unnecessary because the type is always part of the system definition. However systems often need to handle identifiers where the system is not known. There is not a 1:1 relationship between type and system, since many different systems have the same type. Data Type CodeableConcept Binding A coded type for an identifier that can be used to determine which identifier to use for a specific purpose. Identifier Type Codes (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD v2:CX.5 rim:Role.code or implied by context
system	Σ	0..1	uri	There are no (further) constraints on this element Element Id Observation.derivedFrom.identifier.system Short description The namespace for the identifier value Definition Establishes the namespace for the value - that is, a URL that describes a set values that are unique. Requirements There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers. Comments Identifier.system is always case sensitive. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General http://www.acme.com/identifiers/patient Mappings rim:n/a v2:CX.4 / EI-2-4 rim:II.root or Role.id.root servd:./IdentifierType
value	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.derivedFrom.identifier.value Short description The value that is unique Definition The portion of the identifier typically relevant to the user and which is unique within the context of the system. Comments If the value is a full URI, then the system SHALL be urn:ietf:rfc:3986. The value's primary purpose is computational mapping. As a result, it may be normalized for comparison purposes (e.g. removing non-significant whitespace, dashes, etc.) A value formatted for human display can be conveyed using the Rendered Value extension. Identifier.value is to be treated as case sensitive unless knowledge of the Identifier.system allows the processer to be confident that non-case-sensitive processing is safe. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Examples General 123456 Mappings rim:n/a v2:CX.1 / EI.1 rim:II.extension or II.root if system indicates OID or GUID (Or Role.id.extension or root) servd:./Value
period	Σ I	0..1	Period	There are no (further) constraints on this element Element Id Observation.derivedFrom.identifier.period Short description Time period when id is/was valid for use Definition Time period during which identifier is/was valid for use. Comments A Period specifies a range of time; the context of use will specify whether the entire range applies (e.g. "the patient was an inpatient of the hospital for this time range") or one value from the range applies (e.g. "give to the patient between these two times"). Period is not used for a duration (a measure of elapsed time). See Duration. Data Type Period Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` per-1:If present, start SHALL have a lower value than end `start.hasValue().not() or end.hasValue().not() or (start <= end)` Mappings rim:n/a v2:DR rim:IVL<TS>[lowClosed="true" and highClosed="true"] or URG<TS>[lowClosed="true" and highClosed="true"] v2:CX.7 + CX.8 rim:Role.effectiveTime or implied by context servd:./StartDate and ./EndDate
assigner	Σ I	0..1	Reference(UK Core Organization)	There are no (further) constraints on this element Element Id Observation.derivedFrom.identifier.assigner Short description Organization that issued id (may be just text) Definition Organization that issued/manages the identifier. Comments The Identifier.assigner may omit the .reference element and only contain a .display element reflecting the name or other textual information about the assigning organization. Data Type Reference(UK Core Organization) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` ref-1:SHALL have a contained resource if a local reference is provided `reference.startsWith('#').not() or (reference.substring(1).trace('url') in %rootResource.contained.id.trace('ids'))` Mappings rim:n/a rim:The target of a resource reference is a RIM entry point (Act, Role, or Entity) v2:CX.4 / (CX.4,CX.9,CX.10) rim:II.assigningAuthorityName but note that this is an improper use by the definition of the field. Also Role.scoper servd:./IdentifierIssuingAuthority
display	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.derivedFrom.display Short description Text alternative for the resource Definition Plain text narrative that identifies the resource in addition to the resource reference. Comments This is generally not the same as the Resource.text of the referenced resource. The purpose is to identify what's being referenced, not to fully describe it. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a rim:N/A
component	Σ	0..*	BackboneElement	There are no (further) constraints on this element Element Id Observation.component Short description Component results Definition Some observations have multiple component observations. These component observations are expressed as separate code value pairs that share the same attributes. Examples include systolic and diastolic component observations for blood pressure measurement and multiple component observations for genetics observations. Requirements Component observations share the same attributes in the Observation resource as the primary observation and are always treated a part of a single observation (they are not separable). However, the reference range for the primary observation value is not inherited by the component values and is required when appropriate for each component observation. Comments For a discussion on the ways Observations can be assembled in groups together see Notes below. Data Type BackboneElement Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:containment by OBX-4? rim:outBoundRelationship[typeCode=COMP]
code	Σ	1..1	CodeableConcept	There are no (further) constraints on this element Element Id Observation.component.code Short description Type of component observation (code / type) Definition Describes what was observed. Sometimes this is called the observation "code". Requirements Knowing what kind of observation is being made is essential to understanding the observation. Comments All code-value and component.code-component.value pairs need to be taken into account to correctly understand the meaning of the observation. Data Type CodeableConcept Binding Codes identifying names of simple observations. LOINCCodes (example) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD w5:FiveWs.what[x] sct-concept:< 363787002 \|Observable entity\| OR < 386053000 \|Evaluation procedure\| v2:OBX-3 rim:code
coding	Σ	0..*	Coding	There are no (further) constraints on this element Element Id Observation.component.code.coding Short description Code defined by a terminology system Definition A reference to a code defined by a terminology system. Requirements Allows for alternative encodings within a code system, and translations to other code systems. Comments Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. Data Type Coding Sliced: Unordered, Open, by code(Value), system(Value) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE subset one of the sets of component 1-3 or 4-6 rim:CV orim:fhir:Coding rdfs:subClassOf dt:CDCoding v2:CE.1-8, CE.10-22 rim:union(., ./translation) orim:fhir:CodeableConcept.coding rdfs:subPropertyOf dt:CD.coding
snomedCT	Σ	0..*	CodingBinding	There are no (further) constraints on this element Element Id Observation.component.code.coding:snomedCT Short description Code defined by a terminology system Definition A reference to a code defined by a terminology system. Requirements Allows for alternative encodings within a code system, and translations to other code systems. Comments Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labeled as UserSelected = true. Data Type Coding Binding A code from the SNOMED Clinical Terminology UK coding system describing a type of observation UKCoreObservationType (preferred) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE subset one of the sets of component 1-3 or 4-6 rim:CV orim:fhir:Coding rdfs:subClassOf dt:CDCoding v2:CE.1-8, CE.10-22 rim:union(., ./translation) orim:fhir:CodeableConcept.coding rdfs:subPropertyOf dt:CD.coding
system	Σ	1..1	uriFixed Value	There are no (further) constraints on this element Element Id Observation.component.code.coding:snomedCT.system Short description Identity of the terminology system Definition The identification of the code system that defines the meaning of the symbol in the code. Requirements Need to be unambiguous about the source of the definition of the symbol. Comments The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously. Data Type uri Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Fixed Value http://snomed.info/sct Mappings rim:n/a v2:CE.3 rim:./codeSystem orim:*fhir:Coding.system rdfs:subPropertyOf dt:CDCoding.codeSystem
version	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.component.code.coding:snomedCT.version Short description Version of the system - if relevant Definition The version of the code system which was used when choosing this code. Note that a well-maintained code system does not need the version reported, because the meaning of codes is consistent across versions. However this cannot consistently be assured, and when the meaning is not guaranteed to be consistent, the version SHOULD be exchanged. Comments Where the terminology does not clearly define what string should be used to identify code system versions, the recommendation is to use the date (expressed in FHIR date format) on which that version was officially published as the version date. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.7 rim:./codeSystemVersion orim:*fhir:Coding.version rdfs:subPropertyOf dt:CDCoding.codeSystemVersion
code	Σ	1..1	code	There are no (further) constraints on this element Element Id Observation.component.code.coding:snomedCT.code Short description Symbol in syntax defined by the system Definition A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination). Requirements Need to refer to a particular code in the system. Comments Note that FHIR strings SHALL NOT exceed 1MB in size Data Type code Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.1 rim:./code orim:*fhir:Coding.code rdfs:subPropertyOf dt:CDCoding.code
display	Σ	1..1	string	There are no (further) constraints on this element Element Id Observation.component.code.coding:snomedCT.display Short description Representation defined by the system Definition A representation of the meaning of the code in the system, following the rules of the system. Requirements Need to be able to carry a human-readable meaning of the code for readers that do not know the system. Comments Note that FHIR strings SHALL NOT exceed 1MB in size Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.2 - but note this is not well followed rim:CV.displayName orim:*fhir:Coding.display rdfs:subPropertyOf dt:CDCoding.displayName
userSelected	Σ	0..1	boolean	There are no (further) constraints on this element Element Id Observation.component.code.coding:snomedCT.userSelected Short description If this coding was chosen directly by the user Definition Indicates that this coding was chosen by a user directly - e.g. off a pick list of available items (codes or displays). Requirements This has been identified as a clinical safety criterium - that this exact system/code pair was chosen explicitly, rather than inferred by the system based on some rules or language processing. Comments Amongst a set of alternatives, a directly chosen code is the most appropriate starting point for new translations. There is some ambiguity about what exactly 'directly chosen' implies, and trading partner agreement may be needed to clarify the use of this element and its consequences more completely. Data Type boolean Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:Sometimes implied by being first rim:CD.codingRationale orim:fhir:Coding.userSelected fhir:mapsTo dt:CDCoding.codingRationale. fhir:Coding.userSelected fhir:hasMap fhir:Coding.userSelected.map. fhir:Coding.userSelected.map a fhir:Map; fhir:target dt:CDCoding.codingRationale. fhir:Coding.userSelected\#true a [ fhir:source "true"; fhir:target dt:CDCoding.codingRationale\#O ]
text	Σ	0..1	string	There are no (further) constraints on this element Element Id Observation.component.code.text Short description Plain text representation of the concept Definition A human language representation of the concept as seen/selected/uttered by the user who entered the data and/or which represents the intended meaning of the user. Requirements The codes from the terminologies do not always capture the correct meaning with all the nuances of the human using them, or sometimes there is no appropriate code at all. In these cases, the text is used to capture the full meaning of the source. Comments Very often the text is the same as a displayName of one of the codings. Data Type string Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE.9. But note many systems use CE.2 for this rim:./originalText[mediaType/code="text/plain"]/data orim:fhir:CodeableConcept.text rdfs:subPropertyOf dt:CD.originalText
value[x]	Σ	0..1		There are no (further) constraints on this element Element Id Observation.component.value[x] Short description Actual component result Definition The information determined as a result of making the observation, if the information has a simple value. Requirements An observation exists to have a value, though it might not if it is in error, or if it represents a group of observations. Comments Used when observation has a set of component observations. An observation may have both a value (e.g. an Apgar score) and component observations (the observations from which the Apgar score was derived). If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the Notes section below. Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a sct-concept:363714003 \|Interprets\| < 441742003 \|Evaluation finding\| v2:OBX.2, OBX.5, OBX.6 rim:value sct-attr:363714003 \|Interprets\|
valueQuantity			Quantity	There are no (further) constraints on this element Data Type Quantity
valueCodeableConcept			CodeableConcept	There are no (further) constraints on this element Data Type CodeableConcept
valueString			string	There are no (further) constraints on this element Data Type string
valueBoolean			boolean	There are no (further) constraints on this element Data Type boolean
valueInteger			integer	There are no (further) constraints on this element Data Type integer
valueRange			Range	There are no (further) constraints on this element Data Type Range
valueRatio			Ratio	There are no (further) constraints on this element Data Type Ratio
valueSampledData			SampledData	There are no (further) constraints on this element Data Type SampledData
valueTime			time	There are no (further) constraints on this element Data Type time
valueDateTime			dateTime	There are no (further) constraints on this element Data Type dateTime
valuePeriod			Period	There are no (further) constraints on this element Data Type Period
dataAbsentReason	I	0..1	CodeableConceptBinding	There are no (further) constraints on this element Element Id Observation.component.dataAbsentReason Short description Why the component result is missing Definition Provides a reason why the expected value in the element Observation.component.value[x] is missing. Requirements For many results it is necessary to handle exceptional values in measurements. Comments "Null" or exceptional values can be represented two ways in FHIR Observations. One way is to simply include them in the value set and represent the exceptions in the value. For example, measurement values for a serology test could be "detected", "not detected", "inconclusive", or "test not done". The alternate way is to use the value element for actual observations and use the explicit dataAbsentReason element to record exceptional values. For example, the dataAbsentReason code "error" could be used when the measurement was not completed. Because of these options, use-case agreements are required to interpret general observations for exceptional values. Data Type CodeableConcept Binding Codes specifying why the result (`Observation.value[x]`) is missing. DataAbsentReason (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD v2:N/A rim:value.nullFlavor
interpretation		0..*	CodeableConceptBinding	There are no (further) constraints on this element Element Id Observation.component.interpretation Short description High, low, normal, etc. Alternate names Abnormal Flag Definition A categorical assessment of an observation value. For example, high, low, normal. Requirements For some results, particularly numeric results, an interpretation is necessary to fully understand the significance of a result. Comments Historically used for laboratory results (known as 'abnormal flag' ), its use extends to other use cases where coded interpretations are relevant. Often reported as one or more simple compact codes this element is often placed adjacent to the result value in reports and flow sheets to signal the meaning/normalcy status of the result. Data Type CodeableConcept Binding Codes identifying interpretations of observations. ObservationInterpretationCodes (extensible) Constraints ele-1:All FHIR elements must have a @value or children `hasValue() or (children().count() > id.count())` Mappings rim:n/a v2:CE/CNE/CWE rim:CD orim:fhir:CodeableConcept rdfs:subClassOf dt:CD sct-concept:< 260245000 \|Findings values\| v2:OBX-8 rim:interpretationCode sct-attr:363713009 \|Has interpretation\|
referenceRange		0..*	see (referenceRange)	There are no (further) constraints on this element Element Id Observation.component.referenceRange Short description Provides guide for interpretation of component result Definition Guidance on how to interpret the value by comparison to a normal or recommended range. Requirements Knowing what values are considered "normal" can help evaluate the significance of a particular result. Need to be able to provide multiple reference ranges for different contexts. Comments Most observations only have one generic reference range. Systems MAY choose to restrict to only supplying the relevant reference range based on knowledge about the patient (e.g., specific to the patient's age, gender, weight and other factors), but this might not be possible or appropriate. Whenever more than one reference range is supplied, the differences between them SHOULD be provided in the reference range and/or age properties. Mappings v2:OBX.7 rim:outboundRelationship[typeCode=REFV]/target[classCode=OBS, moodCode=EVN]

key	human	severity	expression
patient-reference	subject - An identifier reference or resource reference must be provided	warning	(reference.exists() or (identifier.exists()))
patient-nhs	Supplied NHS Number is outside the English and Welsh NHS Number range or length of the number is wrong.	error	identifier.where(system='https://fhir.nhs.uk/Id/nhs-number').exists().not() or (identifier.where(system='https://fhir.nhs.uk/Id/nhs-number').exists() and identifier.where(system='https://fhir.nhs.uk/Id/nhs-number').value.matches('^([456789]{1}[0-9]{9})$'))
performer	An identifier reference or resource reference must be provided	error	(reference.exists() or identifier.exists())

- SARS-CoV-2-ORGY

Constraint Profiles

name	profile
NHSDigitalObservationCOVID19	https://fhir.nhs.uk/StructureDefinition/NHSDigital-Observation-COVID19

Definition

Measurements and simple assertions made about a patient, device or other subject.

Comment

Used for simple observations such as device measurements, laboratory atomic results, vital signs, height, weight, smoking status, comments, etc. Other resources are used to provide context for observations such as laboratory reports, etc.

Constraints

obs-6 (ERROR) dataAbsentReason SHALL only be present if Observation.value is not present
obs-7 (ERROR) If Observation.code is the same as an Observation.component.code then the value element associated with the code SHALL NOT be present
extension:covid19Testing
identifier
status
category
category.coding.system
category.coding.code
category:COVID-TestPillar
category:COVID-TestPillar.coding.system
category:UKCoreCategory
category:UKCoreCategory.coding.system
code
code.coding:snomedCT
code.coding:snomedCT.system
code.coding:loinc
code.coding:loinc.system
subject
subject.identifier.system
effective
performer
value
bodySite.coding:snomedCT
bodySite.coding:snomedCT.system
method
specimen
device
component.code.coding:snomedCT
component.code.coding:snomedCT.system

extension:covid19Testing


Element Id	Observation.extension:covid19Testing
Cardinality	0..1
Slice Name	covid19Testing
type	Extension(ExtensionCOVID19TestResult)

Definition

Optional Extension Element - found in all resources.

identifier


Element Id	Observation.identifier
Cardinality	1..*
type	Identifier

Definition

A unique identifier assigned to this observation.

For COVID-19 Test History this will be The identifier will be the specimen id.


    "identifier":  [
        {
            "system": "https://fhir.nhs.uk/Id/SpecimenId",
            "value": "eb89a392-5b20-11eb-ae93-0242ac130002"
        }
    ],

Requirements

Allows observations to be distinguished and referenced.

status


Element Id	Observation.status
Cardinality	1..1
Terminology Binding	ObservationStatus (Required) Codes providing the status of an observation.
type	code

Definition

The status of the result value.

For COVID-19 Test History the status of the observation will always be final


    "status": "final",

Requirements

Need to track the status of individual results. Some results are finalised before the whole report is finalised.

Comment

This element is labelled as a modifier because the status contains codes that mark the resource as not currently valid.


Element Id	Observation.category
Cardinality	0..*
Terminology Binding	ObservationCategory (Required)
Slicing	OPEN discriminator - VALUE coding.system
type	CodeableConcept

category.coding.system


Element Id	Observation.category.coding.system
Cardinality	1..1
type	uri

Definition

The identification of the code system that defines the meaning of the symbol in the code.

Requirements

Need to be unambiguous about the source of the definition of the symbol.

Comment

The URI may be an OID (urn:oid:...) or a UUID (urn:uuid:...). OIDs and UUIDs SHALL be references to the HL7 OID registry. Otherwise, the URI should come from HL7's list of FHIR defined special URIs or it should reference to some definition that establishes the system clearly and unambiguously.

category.coding.code


Element Id	Observation.category.coding.code
Cardinality	1..1
type	code

Definition

A symbol in syntax defined by the system. The symbol may be a predefined code or an expression in a syntax defined by the coding system (e.g. post-coordination).

Requirements

Need to refer to a particular code in the system.

category:COVID-TestPillar


Element Id	Observation.category:COVID-TestPillar
Cardinality	0..1
Terminology Binding	ObservationCategoryCodes (Preferred) Codes for high level observation categories.
Slice Name	COVID-TestPillar
type	CodeableConcept

Definition

A code that classifies the general type of observation being made.

Requirements

Used for filtering what observations are retrieved and displayed.

Comment

category:COVID-TestPillar.coding.system


Element Id	Observation.category:COVID-TestPillar.coding.system
Cardinality	0..1
Fixed Value	https://fhir.nhs.uk/CodeSystem/covid-test-pillar
type	uri

Definition

The identification of the code system that defines the meaning of the symbol in the code.

Requirements

Need to be unambiguous about the source of the definition of the symbol.

Comment

category:UKCoreCategory


Element Id	Observation.category:UKCoreCategory
Cardinality	0..*
Terminology Binding	ObservationCategoryCodes (Preferred) Codes for high level observation categories.
Slice Name	UKCoreCategory
type	CodeableConcept

Definition

A code that classifies the general type of observation being made.

Requirements

Used for filtering what observations are retrieved and displayed.

Comment

category:UKCoreCategory.coding.system


Element Id	Observation.category:UKCoreCategory.coding.system
Cardinality	0..1
Fixed Value	http://terminology.hl7.org/CodeSystem/observation-category
type	uri

Definition

The identification of the code system that defines the meaning of the symbol in the code.

Requirements

Need to be unambiguous about the source of the definition of the symbol.

Comment

code


Element Id	Observation.code
Cardinality	1..1
Terminology Binding	LOINCCodes (Example) Codes identifying names of simple observations.
type	CodeableConcept

Definition

Type of observation, for COVID-10 see Observation Definition for code values.

    "code": {
        "coding":  [
            {
                "system": "http://snomed.info/sct",
                "code": "871555000",
                "display": "Detection of ribonucleic acid of Severe acute respiratory syndrome coronavirus 2"
            }
        ]
    },

Requirements

Knowing what kind of observation is being made is essential to understanding the observation.

Comment

All code-value and, if present, component.code-component.value pairs need to be taken into account to correctly understand the meaning of the observation.

code.coding:snomedCT


Element Id	Observation.code.coding:snomedCT
Cardinality	0..*
Terminology Binding	UKCoreObservationType (Extensible) A code from the SNOMED Clinical Terminology UK coding system describing a type of observation
Slice Name	snomedCT
type	Coding

Definition

A reference to a code defined by a terminology system.

Requirements

Allows for alternative encodings within a code system, and translations to other code systems.

Comment

Codes may be defined very casually in enumerations, or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information. Ordering of codings is undefined and SHALL NOT be used to infer meaning. Generally, at most only one of the coding values will be labelled as UserSelected = true.

code.coding:snomedCT.system


Element Id	Observation.code.coding:snomedCT.system
Cardinality	1..1
Fixed Value	http://snomed.info/sct
type	uri

Definition

The identification of the code system that defines the meaning of the symbol in the code.

Requirements

Need to be unambiguous about the source of the definition of the symbol.

Comment

code.coding:loinc


Element Id	Observation.code.coding:loinc
Cardinality	0..*
Slice Name	loinc
type	Coding

Definition

A reference to a code defined by a terminology system.

Requirements

Allows for alternative encodings within a code system, and translations to other code systems.

Comment

code.coding:loinc.system


Element Id	Observation.code.coding:loinc.system
Cardinality	1..1
Fixed Value	http://loinc.org
type	uri

Definition

The identification of the code system that defines the meaning of the symbol in the code.

Requirements

Need to be unambiguous about the source of the definition of the symbol.

Comment

subject


Element Id	Observation.subject
Cardinality	1..1
type	Reference(Group Device UKCoreLocation NHSDigitalPatientMinimal)

Definition

The NHS Number will be an identifier reference which can be used with PDS FHIR API to return Patient demographics. If a local Patient is available, a reference to this will be present (e.g. "Patient/123")


    "subject": {
        "reference": "Patient/123",
        "identifier":  [
            {
                "system": "https://fhir.nhs.uk/Id/nhs-number",
                "value": "987123456"
            }
        ]
    },

Requirements

Observations have no value if you don't know who or what they're about.

Comment

One would expect this element to be a cardinality of 1..1. The only circumstance in which the subject can be missing is when the observation is made by a device that does not know the patient. In this case, the observation SHALL be matched to a patient through some context/channel matching technique, and at this point, the observation should be updated.

Constraints

patient-reference (WARNING) subject - An identifier reference or resource reference must be provided
patient-nhs (ERROR) Supplied NHS Number is outside the English and Welsh NHS Number range or length of the number is wrong.

subject.identifier.system


Element Id	Observation.subject.identifier.system
Cardinality	1..1
Fixed Value	https://fhir.nhs.uk/Id/nhs-number
type	uri

Definition

Establishes the namespace for the value - that is, a URL that describes a set values that are unique.

Requirements

There are many sets of identifiers. To perform matching of two identifiers, we need to know what set we're dealing with. The system identifies a particular set of unique identifiers.

Comment

Identifier.system is always case sensitive.

effective[x]


Element Id	Observation.effective[x]
Cardinality	1..1
type	dateTime

Definition

The date and time the result was asserted.


    "effectiveDateTime": "2020-09-23T13:00:08.476+00:00"

Requirements

Knowing when an observation was deemed true is important to its relevance as well as determining trends.

Comment

At least a date should be present unless this observation is a historical report. For recording imprecise or "fuzzy" times (For example, a blood glucose measurement taken "after breakfast") use the Timing datatype which allow the measurement to be tied to regular life events.

performer


Element Id	Observation.performer
Cardinality	0..*
type	Reference(NHSDigitalOrganization CareTeam NHSDigitalPatient NHSDigitalPractitionerRoleMinimal NHSDigitalReference)

Definition

Who was responsible for asserting the observed value as "true".


"performer": [
  {
    "type": "Organization",
    "identifier": {
      "type": {
        "coding": [
          {
            "system": "https://fhir.nhs.uk/CodeSystem/organisation-role",
            "code": "173",
            "display": "PATHOLOGY LAB"
          }
        ]
      },
      "value": "LFD004"
    }
  },
  {
    "type": "Organization",
    "identifier": {
      "type": {
        "coding": [
          {
            "system": "https://fhir.nhs.uk/Id/OrgType",
            "code": "TestCentreId",
            "display": "Testing Centre"
          }
        ]
      },
      "value": "WKE03"
    }
  }
]

Requirements

May give a degree of confidence in the observation and also indicates where follow-up questions should be directed.

Comment

References SHALL be a reference to an actual FHIR resource, and SHALL be resolvable (allowing for access control, temporary unavailability, etc.). Resolution can be either by retrieval from the URL, or, where applicable by resource type, by treating an absolute reference as a canonical URL and looking it up in a local registry/repository.

Constraints

performer (ERROR) An identifier reference or resource reference must be provided

value[x]


Element Id	Observation.value[x]
Cardinality	0..1
type	Quantity CodeableConcept string boolean integer Range Ratio SampledData time dateTime Period

Definition

COVID-19 valueCodeableConcept

The COVID 19 test result. This is a SNOMED CT from the valueSet associated with the code, see Observation Definition


    "valueCodeableConcept": {
        "coding":  [
            {
                "system": "http://snomed.info/sct",
                "code": "1240581000000104",
                "display": "SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) detection result positive"
            }
        ],
        "text": "SARS-CoV-2-ORGY"
    },

Requirements

An observation exists to have a value, though it might not if it is in error, or if it represents a group of observations.

Comment

An observation may have; 1) a single value here, 2) both a value and a set of related or component values, or 3) only a set of related or component values. If a value is present, the datatype for this element should be determined by Observation.code. A CodeableConcept with just a text would be used instead of a string if the field was usually coded, or if the type associated with the Observation.code defines a coded value. For additional guidance, see the Notes section below.

bodySite.coding:snomedCT


Element Id	Observation.bodySite.coding:snomedCT
Cardinality	0..1
Terminology Binding	UKCoreBodySite (Extensible) A code from the SNOMED Clinical Terminology UK with the expression (<<442083009	anatomical or acquired body structure	)
Slice Name	snomedCT
type	Coding

Definition

A reference to a code defined by a terminology system.

Requirements

Allows for alternative encodings within a code system, and translations to other code systems.

Comment

bodySite.coding:snomedCT.system


Element Id	Observation.bodySite.coding:snomedCT.system
Cardinality	1..1
Fixed Value	http://snomed.info/sct
type	uri

Definition

The identification of the code system that defines the meaning of the symbol in the code.

Requirements

Need to be unambiguous about the source of the definition of the symbol.

Comment

method


Element Id	Observation.method
Cardinality	0..1
Terminology Binding	ObservationMethods (Extensible)
type	CodeableConcept

Definition

The name of the test that was performed, this is a SNOMED CT concept.


    "method": {
        "coding":  [
            {
                "system": "http://snomed.info/sct",
                "code": "1240461000000109",
                "display": "Measurement of SARS-CoV-2 antibody (procedure)"
            }
        ]
    },

Requirements

In some cases, method can impact results and is thus used for determining whether results can be compared or determining significance of results.

Comment

Only used if not implicit in code for Observation.code.

specimen


Element Id	Observation.specimen
Cardinality	0..1
type	Reference(Specimen)

Definition

For COVID-19 Test History. The identifier of the specimen used for the test.


    "specimen": {
        "identifier": {
            "system": "https://fhir.nhs.uk/Id/SpecimenId",
            "value": "eb89a392-5b20-11eb-ae93-0242ac130002"
        }
    },

Comment

Should only be used if not implicit in code found in Observation.code. Observations are not made on specimens themselves; they are made on a subject, but in many cases by the means of a specimen. Note that although specimens are often involved, they are not always tracked and reported explicitly. Also note that observation resources may be used in contexts that track the specimen explicitly (e.g. Diagnostic Report).

device


Element Id	Observation.device
Cardinality	0..1
type	Reference(Device DeviceMetric)

Definition

Details of the COVID-19 test kit used.


    "device": {
        "identifier": {
            "system": "https://fhir.nhs.uk/Id/Covid19-TestKit",
            "value": "LFT"
        },
        "display": "Lateral Flow Test"
    }

Comment

Note that this is not meant to represent a device involved in the transmission of the result, e.g., a gateway. Such devices may be documented using the Provenance resource where relevant.

component.code.coding:snomedCT


Element Id	Observation.component.code.coding:snomedCT
Cardinality	0..*
Terminology Binding	UKCoreObservationType (Extensible) A code from the SNOMED Clinical Terminology UK coding system describing a type of observation
Slice Name	snomedCT
type	Coding

Definition

A reference to a code defined by a terminology system.

Requirements

Allows for alternative encodings within a code system, and translations to other code systems.

Comment

component.code.coding:snomedCT.system


Element Id	Observation.component.code.coding:snomedCT.system
Cardinality	1..1
Fixed Value	http://snomed.info/sct
type	uri

Definition

The identification of the code system that defines the meaning of the symbol in the code.

Requirements

Need to be unambiguous about the source of the definition of the symbol.