NHSDigital-Observation
| Conformance url | FHIR Module | Maturity Level |
|---|---|---|
| https://fhir.nhs.uk/StructureDefinition/NHSDigital-Observation | Diagnostics | trial-use |
Combined with
| NHSDigitalObservation (Observation) | https://fhir.hl7.org.uk/StructureDefinition/UKCore-Observation | ||
| extension | 0.. | ||
| covid19Testing | S | 0..1 | Extension(Complex) |
| identifier | S | 1.. | |
| system | 1.. | ||
| value | 1.. | ||
| status | S | ||
| category | S | Binding | |
| (All Slices) | |||
| coding | 1.. | ||
| system | S | 1.. | |
| code | S | 1.. | |
| COVID-TestPillar | ..1 | ||
| coding | |||
| system | Fixed Value | ||
| UKCoreCategory | |||
| coding | |||
| system | Fixed Value | ||
| code | S | ||
| subject | S C | 1.. | Reference(Device | Group | https://fhir.hl7.org.uk/StructureDefinition/UKCore-Location | NHSDigitalPatientMinimal) |
| identifier | |||
| system | 1.. | Fixed Value | |
| value | 1.. | ||
| effective[x] | S | 1.. | |
| effectiveDateTime | dateTime | ||
| performer | S C | NHSDigitalReference(CareTeam | NHSDigitalOrganization | NHSDigitalPatient | NHSDigitalPractitionerRoleMinimal) | |
| value[x] | S | ||
| method | S | ||
| coding | |||
| system | 1.. | ||
| code | 1.. | ||
| display | 1.. | ||
| specimen | S | ||
| identifier | |||
| system | 1.. | ||
| value | 1.. | ||
| device | S | ||
| identifier | |||
| system | 1.. | ||
| value | 1.. | ||
| display | 1.. |
from
| NHSDigitalObservation (Observation) | https://fhir.hl7.org.uk/StructureDefinition/UKCore-Observation | ||
| extension | 0.. | ||
| covid19Testing | S | 0..1 | Extension(Complex) |
| identifier | S | 1.. | |
| system | 1.. | ||
| value | 1.. | ||
| status | S | ||
| category | S | Binding | |
| (All Slices) | |||
| coding | 1.. | ||
| system | S | 1.. | |
| code | S | 1.. | |
| COVID-TestPillar | ..1 | ||
| coding | |||
| system | Fixed Value | ||
| UKCoreCategory | |||
| coding | |||
| system | Fixed Value | ||
| code | S | ||
| subject | S C | 1.. | Reference(Device | Group | https://fhir.hl7.org.uk/StructureDefinition/UKCore-Location | NHSDigitalPatientMinimal) |
| identifier | |||
| system | 1.. | Fixed Value | |
| value | 1.. | ||
| effective[x] | S | 1.. | |
| effectiveDateTime | dateTime | ||
| performer | S C | NHSDigitalReference(CareTeam | NHSDigitalOrganization | NHSDigitalPatient | NHSDigitalPractitionerRoleMinimal) | |
| value[x] | S | ||
| method | S | ||
| coding | |||
| system | 1.. | ||
| code | 1.. | ||
| display | 1.. | ||
| specimen | S | ||
| identifier | |||
| system | 1.. | ||
| value | 1.. | ||
| device | S | ||
| identifier | |||
| system | 1.. | ||
| value | 1.. | ||
| display | 1.. |
-
Constraint Profiles
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
| 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 finalized before the whole report is finalized.
Comment
This element is labeled as a modifier because the status contains codes that mark the resource as not currently valid.
category
| Element Id | Observation.category |
| Cardinality | 0..* |
| Terminology Binding | ObservationCategory (Required) |
| Slicing | OPEN discriminator - VALUE coding.system |
| type | CodeableConcept |
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.
Comment
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.
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
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.
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
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: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
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.
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
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.
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 labeled 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
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.
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
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.
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
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.
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 NHSDigitalPractitionerRoleMinimalNHSDigitalReference) |
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 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.
Constraints
- performer (ERROR) An identifier reference or resource reference must be provided
value[x]
| Element Id | Observation.value[x] |
| Cardinality | 0..1 |
| type | QuantityCodeableConceptstringbooleanintegerRangeRatioSampledDatatimedateTimePeriod |
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
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.
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
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.
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
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.
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.
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.