XML
<definition value="A process where a researcher or organization plans and then executes a series of steps intended to increase the field of healthcare-related knowledge. This includes studies of safety, efficacy, comparative effectiveness and other information about medications, devices, therapies and other interventional and investigative techniques. A ResearchStudy involves the gathering of information about human or animal subjects." />
</base>
<human value="If the resource is contained in another resource, it SHALL NOT contain nested Resources" />
</constraint>
<human value="If the resource is contained in another resource, it SHALL NOT contain any narrative" />
</constraint>
<human value="If a resource is contained in another resource, it SHALL NOT have a meta.versionId or a meta.lastUpdated" />
<xpath value="not(exists(f:contained/*/f:meta/f:versionId)) and not(exists(f:contained/*/f:meta/f:lastUpdated))" />
</constraint>
<human value="If the resource is contained in another resource, it SHALL be referred to from elsewhere in the resource" />
<xpath value="not(exists(for $id in f:contained/*/@id return $id[not(ancestor::f:contained/parent::*/descendant::f:reference/@value=concat('#', $id))]))" />
</constraint>
</mapping>
</mapping>
</mapping>
</mapping>
</element>
<definition value="The logical id of the resource, as used in the URL for the resource. Once assigned, this value never changes." />
<comment value="The only time that a resource does not have an id is when it is being submitted to the server using a create operation." />
</base>
</type>
</constraint>
</mapping>
</element>
<definition value="The metadata about the resource. This is content that is maintained by the infrastructure. Changes to the content may not always be associated with version changes to the resource." />
</base>
</type>
</constraint>
</mapping>
</mapping>
</element>
<definition value="A reference to a set of rules that were followed when the resource was constructed, and which must be understood when processing the content." />
<comment value="Asserting this rule set restricts the content to be only understood by a limited set of trading partners. This inherently limits the usefulness of the data in the long term. However, the existing health eco-system is highly fractured, and not yet ready to define, collect, and exchange data in a generally computable sense. Wherever possible, implementers and/or specification writers should avoid using this element. \n\nThis element is labelled as a modifier because the implicit rules may provide additional knowledge about the resource that modifies it's meaning or interpretation." />
</base>
</type>
</constraint>
</mapping>
</element>
<comment value="Language is provided to support indexing and accessibility (typically, services such as text to speech use the language tag). The html language tag in the narrative applies to the narrative. The language tag on the resource may be used to specify the language of other presentations generated from the data in the resource Not all the content has to be in the base language. The Resource.language should not be assumed to apply to the narrative automatically. If a language is specified, it should it also be specified on the div element in the html (see rules in HTML5 for information about the relationship between xml:lang and the html lang attribute)." />
</base>
</type>
</constraint>
</extension>
</extension>
</extension>
</valueSetReference>
</binding>
</mapping>
</element>
<definition value="A human-readable narrative that contains a summary of the resource, and may be used to represent the content of the resource to a human. The narrative need not encode all the structured data, but is required to contain sufficient detail to make it "clinically safe" for a human to just read the narrative. Resource definitions may define what content should be represented in the narrative to ensure clinical safety." />
<comment value="Contained resources do not have narrative. Resources that are not contained SHOULD have a narrative. In some cases, a resource may only have text with little or no additional discrete data (as long as all minOccurs=1 elements are satisfied). This may be necessary for data from legacy systems where information is captured as a "text blob" or where text is additionally entered raw or narrated and encoded in formation is added later." />
</base>
</type>
</constraint>
</mapping>
</mapping>
</mapping>
</element>
<definition value="These resources do not have an independent existence apart from the resource that contains them - they cannot be identified independently, and nor can they have their own independent transaction scope." />
<comment value="This should never be done when the content can be identified properly, as once identification is lost, it is extremely difficult (and context dependent) to restore it again." />
</base>
</type>
</mapping>
</mapping>
</element>
</discriminator>
</slicing>
<definition value="May be used to represent additional information that is not part of the basic definition of the resource. In order 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 is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension." />
<comment value="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." />
</base>
</type>
</constraint>
</constraint>
</mapping>
</mapping>
</element>
</discriminator>
</slicing>
<definition value="May be used to represent additional information that is not part of the basic definition of the resource, and that modifies the understanding of the element that contains it. Usually modifier elements provide negation or qualification. In order 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 is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions." />
<comment value="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." />
</base>
</type>
</constraint>
</constraint>
</mapping>
</mapping>
</element>
<requirements value="Allows identification of the research study as it is known by various participating systems and in a way that remains consistent across servers." />
</base>
</type>
</constraint>
</mapping>
</mapping>
<map value="II - see see identifier pattern at http://wiki.hl7.org/index.php?title=Common_Design_Patterns#Identifier_Pattern for relevant discussion. 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]" />
</mapping>
</mapping>
</mapping>
</mapping>
</mapping>
</element>
<definition value="unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces." />
</base>
</type>
</constraint>
</mapping>
</element>
</discriminator>
</slicing>
<definition value="May be used to represent additional information that is not part of the basic definition of the element. In order 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 is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension." />
<comment value="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." />
</base>
</type>
</constraint>
</constraint>
</mapping>
</mapping>
</element>
<comment value="This is labeled as "Is Modifier" because applications should not mistake a temporary id for a permanent one. Applications can assume that an identifier is permanent unless it explicitly says that it is temporary." />
<requirements value="Allows the appropriate identifier for a particular context of use to be selected from among a set of identifiers." />
</base>
</type>
</constraint>
</extension>
</valueSetReference>
</binding>
</mapping>
</mapping>
</mapping>
</element>
<definition value="A coded type for the identifier that can be used to determine which identifier to use for a specific purpose." />
<comment value="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. \n\nWhere 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." />
<requirements value="Allows users to make use of identifiers when the identifier system is not known." />
</base>
</type>
</constraint>
</extension>
</extension>
<description value="A coded type for an identifier that can be used to determine which identifier to use for a specific purpose." />
</valueSetReference>
</binding>
</mapping>
</mapping>
</mapping>
</mapping>
</mapping>
</mapping>
</element>
<definition value="Establishes the namespace for the value - that is, a URL that describes a set values that are unique." />
<requirements value="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." />
</base>
</type>
</example>
</constraint>
</binding>
</mapping>
</mapping>
</mapping>
</mapping>
</element>
<definition value="The portion of the identifier typically relevant to the user and which is unique within the context of the system." />
<comment value="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](extension-rendered-value.html)." />
</base>
</type>
</example>
</constraint>
</mapping>
</mapping>
<map value="II.extension or II.root if system indicates OID or GUID (Or Role.id.extension or root)" />
</mapping>
</mapping>
</element>
<comment value="This is not a duration - that's a measure of time (a separate type), but a duration that occurs at a fixed value of time. 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"). If duration is required, specify the type as Interval|Duration." />
</base>
</type>
</constraint>
</constraint>
</mapping>
</mapping>
<map value="IVL<TS>[lowClosed="true" and highClosed="true"] or URG<TS>[lowClosed="true" and highClosed="true"]" />
</mapping>
</mapping>
</mapping>
</mapping>
</element>
<comment value="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." />
</base>
</type>
</constraint>
<expression value="reference.startsWith('#').not() or (reference.substring(1).trace('url') in %resource.contained.id.trace('ids'))" />
<xpath value="not(starts-with(f:reference/@value, '#')) or exists(ancestor::*[self::f:entry or self::f:parameter]/f:resource/f:*/f:contained/f:*[f:id/@value=substring-after(current()/f:reference/@value, '#')]|/*/f:contained/f:*[f:id/@value=substring-after(current()/f:reference/@value, '#')])" />
</constraint>
</mapping>
</mapping>
</mapping>
<map value="II.assigningAuthorityName but note that this is an improper use by the definition of the field. Also Role.scoper" />
</mapping>
</mapping>
</element>
</base>
</type>
</constraint>
</mapping>
</mapping>
</element>
<definition value="The set of steps expected to be performed as part of the execution of the study." />
<comment value="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." />
</base>
</type>
</constraint>
<expression value="reference.startsWith('#').not() or (reference.substring(1).trace('url') in %resource.contained.id.trace('ids'))" />
<xpath value="not(starts-with(f:reference/@value, '#')) or exists(ancestor::*[self::f:entry or self::f:parameter]/f:resource/f:*/f:contained/f:*[f:id/@value=substring-after(current()/f:reference/@value, '#')]|/*/f:contained/f:*[f:id/@value=substring-after(current()/f:reference/@value, '#')])" />
</constraint>
</mapping>
</mapping>
</mapping>
</mapping>
</element>
<definition value="A larger research study of which this particular study is a component or step." />
<comment value="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." />
<requirements value="Allows breaking a study into components (e.g. by study site) each with their own PI, status, enrollment, etc." />
</base>
</type>
</constraint>
<expression value="reference.startsWith('#').not() or (reference.substring(1).trace('url') in %resource.contained.id.trace('ids'))" />
<xpath value="not(starts-with(f:reference/@value, '#')) or exists(ancestor::*[self::f:entry or self::f:parameter]/f:resource/f:*/f:contained/f:*[f:id/@value=substring-after(current()/f:reference/@value, '#')]|/*/f:contained/f:*[f:id/@value=substring-after(current()/f:reference/@value, '#')])" />
</constraint>
</mapping>
</mapping>
</mapping>
</element>
<comment value="This element is labeled as a modifier because the status contains codes that mark the resource as not currently valid." />
</base>
</type>
</constraint>
</extension>
</valueSetReference>
</binding>
</mapping>
</mapping>
</mapping>
</element>
<definition value="Codes categorizing the type of study such as investigational vs. observational, type of blinding, type of randomization, safety vs. efficacy, etc." />
<comment value="Not all terminology uses fit this general pattern. In some cases, models should not use CodeableConcept and use Coding directly and provide their own structure for managing text, codings, translations and the relationship between elements and pre- and post-coordination." />
</base>
</type>
</constraint>
</extension>
<description value="Codes that describe the type of research study. E.g. Study phase, Interventional/Observational, blinding type, etc." />
</binding>
</mapping>
</mapping>
</mapping>
</mapping>
<map value="Study Type; Primary Purpose; Study Phase; Interventional Model; Masking; Allocation; study Classification; Observational Study Model; Time Perspective; Biospecimen Retention" />
</mapping>
</element>
<definition value="The condition(s), medication(s), food(s), therapy(ies), device(s) or other concerns or interventions that the study is seeking to gain more information about." />
<comment value="Not all terminology uses fit this general pattern. In some cases, models should not use CodeableConcept and use Coding directly and provide their own structure for managing text, codings, translations and the relationship between elements and pre- and post-coordination." />
</base>
</type>
</constraint>
</extension>
</binding>
</mapping>
</mapping>
</mapping>
</mapping>
</mapping>
</mapping>
</element>
<definition value="Contact details to assist a user in learning more about or engaging with the study." />
</base>
</type>
</constraint>
</mapping>
<map value="Central Contact; Central Contact Backup; Overall Study Officials; Facility Contact & Backup (if Study tied to only one location); Investigators" />
</mapping>
</element>
<comment value="Each related artifact is either an attachment, or a reference to another knowledge resource, but not both." />
</base>
</type>
</constraint>
</mapping>
</mapping>
</element>
<comment value="Not all terminology uses fit this general pattern. In some cases, models should not use CodeableConcept and use Coding directly and provide their own structure for managing text, codings, translations and the relationship between elements and pre- and post-coordination." />
</base>
</type>
</constraint>
</extension>
</binding>
</mapping>
</mapping>
</mapping>
</mapping>
</mapping>
</element>
<comment value="Not all terminology uses fit this general pattern. In some cases, models should not use CodeableConcept and use Coding directly and provide their own structure for managing text, codings, translations and the relationship between elements and pre- and post-coordination." />
</base>
</type>
</constraint>
</extension>
</extension>
</valueSetReference>
</binding>
</mapping>
</mapping>
</mapping>
</mapping>
</element>
<comment value="Systems are not required to have markdown support, and there is considerable variation in markdown syntax, so the text should be readable without markdown processing. The preferred markdown syntax is described here: http://daringfireball.net/projects/markdown/syntax (and tests here: http://daringfireball.net/projects/downloads/MarkdownTest_1.0.zip)" />
</base>
</type>
</constraint>
</mapping>
</mapping>
</element>
<definition value="Reference to a Group that defines the criteria for and quantity of subjects participating in the study. E.g. " 200 female Europeans between the ages of 20 and 45 with early onset diabetes"." />
<comment value="The Group referenced should not generally enumerate specific subjects. Subjects will be linked to the study using the ResearchSubject resource." />
</base>
</type>
</constraint>
<expression value="reference.startsWith('#').not() or (reference.substring(1).trace('url') in %resource.contained.id.trace('ids'))" />
<xpath value="not(starts-with(f:reference/@value, '#')) or exists(ancestor::*[self::f:entry or self::f:parameter]/f:resource/f:*/f:contained/f:*[f:id/@value=substring-after(current()/f:reference/@value, '#')]|/*/f:contained/f:*[f:id/@value=substring-after(current()/f:reference/@value, '#')])" />
</constraint>
</mapping>
</mapping>
<map value="Enrollment; Number of Groups/Cohorts (= number of "enrollment" instances); Groups (Group/Cohort Label = Group.name; Group/Cohort Description = Group.description); Eligibility (Group criteria)" />
</mapping>
</mapping>
</element>
<definition value="Identifies the start date and the expected (or actual, depending on status) end date for the study." />
<comment value="This is not a duration - that's a measure of time (a separate type), but a duration that occurs at a fixed value of time. 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"). If duration is required, specify the type as Interval|Duration." />
<requirements value="[The list of types may be constrained as appropriate for the type of event]." />
</base>
</type>
</constraint>
</constraint>
</mapping>
</mapping>
<map value="IVL<TS>[lowClosed="true" and highClosed="true"] or URG<TS>[lowClosed="true" and highClosed="true"]" />
</mapping>
</mapping>
</mapping>
</element>
<comment value="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." />
</base>
</type>
</constraint>
<expression value="reference.startsWith('#').not() or (reference.substring(1).trace('url') in %resource.contained.id.trace('ids'))" />
<xpath value="not(starts-with(f:reference/@value, '#')) or exists(ancestor::*[self::f:entry or self::f:parameter]/f:resource/f:*/f:contained/f:*[f:id/@value=substring-after(current()/f:reference/@value, '#')]|/*/f:contained/f:*[f:id/@value=substring-after(current()/f:reference/@value, '#')])" />
</constraint>
</mapping>
</mapping>
</mapping>
</mapping>
</element>
<definition value="unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces." />
</base>
</type>
</constraint>
</mapping>
</element>
</discriminator>
</slicing>
<definition value="May be used to represent additional information that is not part of the basic definition of the element. In order 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 is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension." />
<comment value="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." />
</base>
</type>
</constraint>
</constraint>
</mapping>
</mapping>
</element>
<definition value="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." />
<comment value="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." />
</base>
</type>
</constraint>
</mapping>
</mapping>
</element>
<definition value="An identifier for the other resource. This is used when there is no way to reference the other resource directly, either because the entity 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." />
<comment value="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. \n\nWhen 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\n\nApplications converting a logical reference to a literal reference may choose to leave the logical reference present, or remove it." />
</base>
</type>
</constraint>
</mapping>
</mapping>
<map value="II - see see identifier pattern at http://wiki.hl7.org/index.php?title=Common_Design_Patterns#Identifier_Pattern for relevant discussion. 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]" />
</mapping>
</mapping>
</mapping>
</element>
</extension>
<definition value="Plain text narrative that identifies the resource in addition to the resource reference." />
<comment value="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." />
</base>
</type>
</constraint>
</mapping>
</mapping>
</element>
<definition value="Indicates the individual who has primary oversite of the execution of the study." />
<comment value="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." />
</base>
</type>
</constraint>
<expression value="reference.startsWith('#').not() or (reference.substring(1).trace('url') in %resource.contained.id.trace('ids'))" />
<xpath value="not(starts-with(f:reference/@value, '#')) or exists(ancestor::*[self::f:entry or self::f:parameter]/f:resource/f:*/f:contained/f:*[f:id/@value=substring-after(current()/f:reference/@value, '#')]|/*/f:contained/f:*[f:id/@value=substring-after(current()/f:reference/@value, '#')])" />
</constraint>
</mapping>
</mapping>
</mapping>
</mapping>
</element>
<definition value="Clinic, hospital or other healthcare location that is participating in the study." />
<comment value="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." />
</base>
</type>
</constraint>
<expression value="reference.startsWith('#').not() or (reference.substring(1).trace('url') in %resource.contained.id.trace('ids'))" />
<xpath value="not(starts-with(f:reference/@value, '#')) or exists(ancestor::*[self::f:entry or self::f:parameter]/f:resource/f:*/f:contained/f:*[f:id/@value=substring-after(current()/f:reference/@value, '#')]|/*/f:contained/f:*[f:id/@value=substring-after(current()/f:reference/@value, '#')])" />
</constraint>
</mapping>
</mapping>
</mapping>
</mapping>
</element>
<comment value="Not all terminology uses fit this general pattern. In some cases, models should not use CodeableConcept and use Coding directly and provide their own structure for managing text, codings, translations and the relationship between elements and pre- and post-coordination." />
</base>
</type>
</constraint>
</mapping>
</mapping>
</mapping>
</mapping>
</mapping>
</mapping>
</element>
<definition value="Comments made about the event by the performer, subject or other participants." />
<comment value="For systems that do not have structured annotations, they can simply communicate a single annotation with no author or time. This element may need to be included in narrative because of the potential for modifying information. *Annotations SHOULD NOT* be used to communicate "modifying" information that could be computable. (This is a SHOULD because enforcing user behavior is nearly impossible)." />
</base>
</type>
</constraint>
</mapping>
</mapping>
</mapping>
</element>
<definition value="Describes an expected sequence of events for one of the participants of a study. E.g. Exposure to drug A, wash-out, exposure to drug B, wash-out, follow-up." />
</base>
</type>
</constraint>
</mapping>
</mapping>
</element>
<definition value="unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces." />
</base>
</type>
</constraint>
</mapping>
</element>
</discriminator>
</slicing>
<definition value="May be used to represent additional information that is not part of the basic definition of the element. In order 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 is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension." />
<comment value="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." />
</base>
</type>
</constraint>
</constraint>
</mapping>
</mapping>
</element>
<definition value="May be used to represent additional information that is not part of the basic definition of the element, and that modifies the understanding of the element that contains it. Usually modifier elements provide negation or qualification. In order 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 is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions." />
<comment value="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." />
</base>
</type>
</constraint>
</constraint>
</mapping>
</mapping>
</element>
</base>
</type>
</constraint>
</mapping>
</mapping>
</element>
<definition value="Categorization of study arm, e.g. experimental, active comparator, placebo comparater." />
<comment value="Not all terminology uses fit this general pattern. In some cases, models should not use CodeableConcept and use Coding directly and provide their own structure for managing text, codings, translations and the relationship between elements and pre- and post-coordination." />
</base>
</type>
</constraint>
</mapping>
</mapping>
</mapping>
</mapping>
</mapping>
</element>
<definition value="A succinct description of the path through the study that would be followed by a subject adhering to this arm." />
</base>
</type>
</constraint>
</mapping>
</mapping>
</element>
</snapshot>
</element>
</binding>
</element>
</element>
</element>
</element>
</element>
</element>
</element>
</element>
</element>
</element>
</element>
</element>
</element>
</element>
</element>
</element>
</differential>
</StructureDefinition>