FHIR Application Feature Framework Implementation Guide
1.0.0-ballot - STU1 Ballot International flag

FHIR Application Feature Framework Implementation Guide, published by HL7 International / FHIR Infrastructure. This guide is not an authorized publication; it is the continuous build for version 1.0.0-ballot built by the FHIR (HL7® FHIR® Standard) CI Build. This version is based on the current content of https://github.com/HL7/capstmt/ and changes regularly. See the Directory of published versions

Logical Model: FeatureDefinition - Detailed Descriptions

Page standards status: Trial-use Maturity Level: 1

Definitions for the FeatureDefinition logical model.

Guidance on how to interpret the contents of this table can be found here

0. FeatureDefinition
Definition

A definition of a feature that applications may implement, or be required to implement. Features are an aspect of a an applications implementation that generally impacts on the handling of data received from or provided to from the application, which makes it worth declaring. Once declared,

ShortFeature Definition
Logical ModelInstances of this logical model are not marked to be the target of a Reference
2. FeatureDefinition.valueType
Definition

Features are very boolean: true or false for whether the application implements the feature, but the value associated with the feature might be a number, a string, or some kind of code

ShortType of value associated with the feature
Control1..1
BindingThe codes SHALL be taken from FHIRTypes
(required to http://hl7.org/fhir/ValueSet/data-types)
Typecode
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
4. FeatureDefinition.valueSet
Definition

If a value set is specified, the value of the data type must come from the value set, and the value type must be one of the bindeable types defined in the FHIR specification

ShortValueSet that controls what coded value are allowed
Control0..1
Typecanonical(ValueSet)
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
6. FeatureDefinition.context
Definition

The elements on which this feature can be defined. These URLs take the form or Canonica(StructureDefinition)#{element-id}, where The structure definition is a reference to a FHIR resource - usually CapabilityStatement of TerminologyCapabilities, and the element-id is a defined element within one of the resources. This is used to state where the feature applies. some features are defined on applications, but others apply to particular resources, or operations on resources, or particular code systems etc

ShortThe FHIR elements on which this feature can be defined
Control0..*
Typeurl
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
8. FeatureDefinition.qualifier
Definition

A qualifier is an extra piece of information that MAY or SHALL be provided when the feature is described/specified that provides additional information about the feature. E.g. a feature defined on a resource may only be applicable to particular events associated with the resource, or ...?

ShortA qualifier that might provided more information about a feature implementation
Control0..*
TypeBackboneElement
10. FeatureDefinition.qualifier.name
Definition

The name of the feature

ShortThe name of the feature
Control1..1
Typecode
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
12. FeatureDefinition.qualifier.description
Definition

A human-readable description of the qualifier.

ShortA human-readable description of the qualifier.
Control0..1
Typestring
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
14. FeatureDefinition.qualifier.valueType
Definition

Features are very boolean: true or false for whether the application implements the feature, but the value associated with the feature might be a number, a string, or some kind of code

ShortType of value associated with the feature
Control1..1
BindingThe codes SHALL be taken from FHIRTypes
(required to http://hl7.org/fhir/ValueSet/data-types)
Typecode
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
16. FeatureDefinition.qualifier.optional
Definition

Whether the feature is optional, or must always be present when a feature is referred to

ShortWhether the feature is optional, or must always be present
Control1..1
Typeboolean
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension

Guidance on how to interpret the contents of this table can be found here

0. FeatureDefinition
Definition

A definition of a feature that applications may implement, or be required to implement. Features are an aspect of a an applications implementation that generally impacts on the handling of data received from or provided to from the application, which makes it worth declaring. Once declared,


Common Interface declaration for conformance and knowledge artifact resources.

ShortFeature DefinitionCommon Interface declaration for definitional resources
Control1..1
Is Modifierfalse
Must Supportfalse
Logical ModelInstances of this logical model are not marked to be the target of a Reference
Summaryfalse
Invariantscnl-0: Name should be usable as an identifier for the module by machine processing applications such as code generation (name.exists() implies name.matches('^[A-Z]([A-Za-z0-9_]){1,254}$'))
dom-2: If the resource is contained in another resource, it SHALL NOT contain nested Resources (contained.contained.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().ofType(canonical) | %resource.descendants().ofType(uri) | %resource.descendants().ofType(url))) or descendants().where(reference = '#').exists() or descendants().where(ofType(canonical) = '#').exists() or descendants().where(ofType(canonical) = '#').exists()).not()).trace('unmatched', id).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-5: If a resource is contained in another resource, it SHALL NOT have a security label (contained.meta.security.empty())
dom-6: A resource should have narrative for robust management (text.`div`.exists())
2. FeatureDefinition.implicitRules
Definition

A reference to a set of rules that were followed when the resource was constructed, and which must be understood when processing the content. Often, this is a reference to an implementation guide that defines the special rules along with other profiles etc.

ShortA set of rules under which this content was created
Comments

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. Often, when used, the URL is a reference to an implementation guide that defines these special rules as part of its narrative along with other profiles, value sets, etc.

Control0..1
Typeuri
Is Modifiertrue because This element is labeled as a modifier because the implicit rules may provide additional knowledge about the resource that modifies its meaning or interpretation
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supportfalse
Summarytrue
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
4. FeatureDefinition.contained
Definition

These resources do not have an independent existence apart from the resource that contains them - they cannot be identified independently, nor can they have their own independent transaction scope. This is allowed to be a Parameters resource if and only if it is referenced by a resource that provides context/meaning.

ShortContained, inline Resources
Comments

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. Contained resources may have profiles and tags in their meta elements, but SHALL NOT have security labels.

Control0..*
This element is affected by the following invariants: dom-2, dom-4, dom-3, dom-5
TypeResource
Is Modifierfalse
Must Supportfalse
Summaryfalse
Alternate Namesinline resources, anonymous resources, contained resources
6. FeatureDefinition.modifierExtension
Definition

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 and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and managable, 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.

Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself).

ShortExtensions that cannot be ignored
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.

Control0..*
TypeExtension
Is Modifiertrue because Modifier extensions are expected to modify the meaning or interpretation of the resource that contains them
Must Supportfalse
Summarytrue
Requirements

Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.

Alternate Namesextensions, user content
Invariantsele-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())
8. FeatureDefinition.status
Definition

The current state of this {{title}}.

Shortdraft | active | retired | unknown
Comments

A nominal state-transition diagram can be found in the Definition pattern documentation.

Unknown does not represent 'other' - one of the defined statuses must apply. Unknown is used when the authoring system is not sure what the current status is.

See guidance around (not) making local changes to elements here.


A nominal state-transition diagram can be found in the Definition pattern documentation.

Unknown does not represent 'other' - one of the defined statuses must apply. Unknown is used when the authoring system is not sure what the current status is.

See guidance around (not) making local changes to elements here.

Control1..1
BindingThe codes SHALL be taken from PublicationStatushttp://hl7.org/fhir/ValueSet/publication-status|5.0.0
(required to http://hl7.org/fhir/ValueSet/publication-status|5.0.0)

The lifecycle status of an artifact.

Typecode
Is Modifiertrue because This is labeled as "Is Modifier" because applications should not use a retired {{title}} without due consideration
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supportfalse
Summarytrue
Requirements

Enables tracking the life-cycle of the content and filtering of {{title}}s that are appropriate for use versus not.

Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
10. FeatureDefinition.valueType
Definition

Features are very boolean: true or false for whether the application implements the feature, but the value associated with the feature might be a number, a string, or some kind of code

ShortType of value associated with the feature
Control1..1
BindingThe codes SHALL be taken from FHIRTypes
(required to http://hl7.org/fhir/ValueSet/data-types)
Typecode
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
12. FeatureDefinition.valueSet
Definition

If a value set is specified, the value of the data type must come from the value set, and the value type must be one of the bindeable types defined in the FHIR specification

ShortValueSet that controls what coded value are allowed
Control0..1
Typecanonical(ValueSet)
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
14. FeatureDefinition.context
Definition

The elements on which this feature can be defined. These URLs take the form or Canonica(StructureDefinition)#{element-id}, where The structure definition is a reference to a FHIR resource - usually CapabilityStatement of TerminologyCapabilities, and the element-id is a defined element within one of the resources. This is used to state where the feature applies. some features are defined on applications, but others apply to particular resources, or operations on resources, or particular code systems etc

ShortThe FHIR elements on which this feature can be defined
Control0..*
Typeurl
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
16. FeatureDefinition.qualifier
Definition

A qualifier is an extra piece of information that MAY or SHALL be provided when the feature is described/specified that provides additional information about the feature. E.g. a feature defined on a resource may only be applicable to particular events associated with the resource, or ...?

ShortA qualifier that might provided more information about a feature implementation
Control0..*
TypeBackboneElement
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
18. FeatureDefinition.qualifier.modifierExtension
Definition

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 in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and managable, 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. Applications processing a resource are required to check for modifier extensions.

Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself).

ShortExtensions that cannot be ignored even if unrecognized
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.

Control0..*
TypeExtension
Is Modifiertrue because Modifier extensions are expected to modify the meaning or interpretation of the element that contains them
Summarytrue
Requirements

Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.

Alternate Namesextensions, user content, modifiers
Invariantsele-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())
20. FeatureDefinition.qualifier.name
Definition

The name of the feature

ShortThe name of the feature
Control1..1
Typecode
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
22. FeatureDefinition.qualifier.description
Definition

A human-readable description of the qualifier.

ShortA human-readable description of the qualifier.
Control0..1
Typestring
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
24. FeatureDefinition.qualifier.valueType
Definition

Features are very boolean: true or false for whether the application implements the feature, but the value associated with the feature might be a number, a string, or some kind of code

ShortType of value associated with the feature
Control1..1
BindingThe codes SHALL be taken from FHIRTypes
(required to http://hl7.org/fhir/ValueSet/data-types)
Typecode
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
26. FeatureDefinition.qualifier.optional
Definition

Whether the feature is optional, or must always be present when a feature is referred to

ShortWhether the feature is optional, or must always be present
Control1..1
Typeboolean
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension

Guidance on how to interpret the contents of this table can be found here

0. FeatureDefinition
Definition

A definition of a feature that applications may implement, or be required to implement. Features are an aspect of a an applications implementation that generally impacts on the handling of data received from or provided to from the application, which makes it worth declaring. Once declared,

ShortFeature Definition
Control1..1
Is Modifierfalse
Must Supportfalse
Logical ModelInstances of this logical model are not marked to be the target of a Reference
Summaryfalse
Invariantscnl-0: Name should be usable as an identifier for the module by machine processing applications such as code generation (name.exists() implies name.matches('^[A-Z]([A-Za-z0-9_]){1,254}$'))
dom-2: If the resource is contained in another resource, it SHALL NOT contain nested Resources (contained.contained.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().ofType(canonical) | %resource.descendants().ofType(uri) | %resource.descendants().ofType(url))) or descendants().where(reference = '#').exists() or descendants().where(ofType(canonical) = '#').exists() or descendants().where(ofType(canonical) = '#').exists()).not()).trace('unmatched', id).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-5: If a resource is contained in another resource, it SHALL NOT have a security label (contained.meta.security.empty())
dom-6: A resource should have narrative for robust management (text.`div`.exists())
2. FeatureDefinition.id
Definition

The logical id of the resource, as used in the URL for the resource. Once assigned, this value never changes.

ShortLogical id of this artifact
Comments

Within the context of the FHIR RESTful interactions, the resource has an id except for cases like the create and conditional update. Otherwise, the use of the resouce id depends on the given use case.

Control0..1
Typeid
Is Modifierfalse
Must Supportfalse
Summarytrue
4. FeatureDefinition.meta
Definition

The metadata about the resource. This is content that is maintained by the infrastructure. Changes to the content might not always be associated with version changes to the resource.

ShortMetadata about the resource
Control0..1
TypeMeta
Is Modifierfalse
Must Supportfalse
Summarytrue
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
6. FeatureDefinition.implicitRules
Definition

A reference to a set of rules that were followed when the resource was constructed, and which must be understood when processing the content. Often, this is a reference to an implementation guide that defines the special rules along with other profiles etc.

ShortA set of rules under which this content was created
Comments

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. Often, when used, the URL is a reference to an implementation guide that defines these special rules as part of its narrative along with other profiles, value sets, etc.

Control0..1
Typeuri
Is Modifiertrue because This element is labeled as a modifier because the implicit rules may provide additional knowledge about the resource that modifies its meaning or interpretation
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supportfalse
Summarytrue
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
8. FeatureDefinition.language
Definition

The base language in which the resource is written.

ShortLanguage of the resource content
Comments

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).

Control0..1
BindingThe codes SHALL be taken from AllLanguages
(required to http://hl7.org/fhir/ValueSet/all-languages|5.0.0)

IETF language tag for a human language

Typecode
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supportfalse
Summaryfalse
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
10. FeatureDefinition.text
Definition

A human-readable narrative that contains a summary of the resource and can 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.

ShortText summary of the resource, for human interpretation
Comments

Contained resources do not have a 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 information is added later.

Control0..1
This element is affected by the following invariants: dom-6
TypeNarrative
Is Modifierfalse
Must Supportfalse
Summaryfalse
Alternate Namesnarrative, html, xhtml, display
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
12. FeatureDefinition.contained
Definition

These resources do not have an independent existence apart from the resource that contains them - they cannot be identified independently, nor can they have their own independent transaction scope. This is allowed to be a Parameters resource if and only if it is referenced by a resource that provides context/meaning.

ShortContained, inline Resources
Comments

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. Contained resources may have profiles and tags in their meta elements, but SHALL NOT have security labels.

Control0..*
This element is affected by the following invariants: dom-2, dom-4, dom-3, dom-5
TypeResource
Is Modifierfalse
Must Supportfalse
Summaryfalse
Alternate Namesinline resources, anonymous resources, contained resources
14. FeatureDefinition.extension
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 managable, 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.

ShortAdditional content defined by implementations
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.

Control0..*
TypeExtension
Is Modifierfalse
Must Supportfalse
Summaryfalse
Alternate Namesextensions, user content
Invariantsele-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())
16. FeatureDefinition.modifierExtension
Definition

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 and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and managable, 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.

Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself).

ShortExtensions that cannot be ignored
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.

Control0..*
TypeExtension
Is Modifiertrue because Modifier extensions are expected to modify the meaning or interpretation of the resource that contains them
Must Supportfalse
Summarytrue
Requirements

Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.

Alternate Namesextensions, user content
Invariantsele-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())
18. FeatureDefinition.url
Definition

An absolute URI that is used to identify this {{title}} when it is referenced in a specification, model, design or an instance; also called its canonical identifier. This SHOULD be globally unique and SHOULD be a literal address at which an authoritative instance of this {{title}} is (or will be) published. This URL can be the target of a canonical reference. It SHALL remain the same when the {{title}} is stored on different servers.

ShortCanonical identifier for this {{title}}, represented as an absolute URI (globally unique)
Comments

Can be a urn:uuid: or a urn:oid: but real http: addresses are preferred. Multiple instances may share the same URL if they have a distinct version.

The determination of when to create a new version of a resource (same url, new version) vs. defining a new artifact is up to the author. Considerations for making this decision are found in Technical and Business Versions.

In some cases, the resource can no longer be found at the stated url, but the url itself cannot change. Implementations can use the meta.source element to indicate where the current master source of the resource can be found.

Control0..1
Typeuri
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supportfalse
Summarytrue
Requirements

Allows the {{title}} to be referenced by a single globally unique identifier.

Invariantscnl-1: URL should not contain | or # - these characters make processing canonical references problematic (exists() implies matches('^[^|# ]+$'))
ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
20. FeatureDefinition.identifier
Definition

A formal identifier that is used to identify this {{title}} when it is represented in other formats, or referenced in a specification, model, design or an instance.

ShortAdditional identifier for the {{title}}
Comments

Typically, this is used for identifiers that can go in an HL7 V3 II (instance identifier) data type, and can then identify this {{title}} outside of FHIR, where it is not possible to use the logical URI.

NoteThis is a business identifier, not a resource identifier (see discussion)
Control0..*
TypeIdentifier
Is Modifierfalse
Must Supportfalse
Summarytrue
Requirements

Allows externally provided and/or usable business identifiers to be easily associated with the {{title}}.

Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
22. FeatureDefinition.version
Definition

The identifier that is used to identify this version of the {{title}} when it is referenced in a specification, model, design or instance. This is an arbitrary value managed by the {{title}} author and is not expected to be globally unique. For example, it might be a timestamp (e.g. yyyymmdd) if a managed version is not available. There is also no expectation that versions can be placed in a lexicographical sequence without additional knowledge. (See the versionAlgorithm element.)

ShortBusiness version of the {{title}}
Comments

There may be different {{title}}s that have the same url but different versions. The version can be appended to the url in a reference to allow a reference to a particular business version of the {{title}} with the format [url]|[version]. The version SHOULD NOT contain a '#' - see Business Version.

NoteThis is a business version Id, not a resource version Id (see discussion)
Control0..1
Typestring
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supportfalse
Summarytrue
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
24. FeatureDefinition.versionAlgorithm[x]
Definition

Indicates the mechanism used to compare versions to determine which is more current.

ShortHow to compare versions
Comments

If set as a string, this is a FHIRPath expression that has two additional context variables passed in - %version1 and %version2 and will return a negative number if version1 is newer, a positive number if version2 and a 0 if the version ordering can't be successfully be determined.

Control0..1
BindingUnless not suitable, these codes SHALL be taken from VersionAlgorithm
(extensible to http://hl7.org/fhir/ValueSet/version-algorithm)
TypeChoice of: string, Coding
[x] NoteSeeChoice of Data Typesfor further information about how to use [x]
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supportfalse
Summarytrue
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
26. FeatureDefinition.name
Definition

A natural language name identifying the {{title}}. This name should be usable as an identifier for the resource by machine processing applications such as code generation.

ShortName for this {{title}} (computer friendly)
Comments

The name is not expected to be globally unique. The name should be a simple alphanumeric type no-whitespace name to ensure that it is machine-processing friendly.

Control0..1
This element is affected by the following invariants: cnl-0
Typestring
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supportfalse
Summarytrue
Requirements

Supports code generation.

Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
28. FeatureDefinition.title
Definition

A short, descriptive, user-friendly title for the {{title}}.

ShortName for this {{title}} (human friendly)
Comments

This name does not need to be machine-processing friendly and may contain punctuation, white-space, etc.

Control0..1
Typestring
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supportfalse
Summarytrue
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
30. FeatureDefinition.status
Definition

The current state of this {{title}}.

Shortdraft | active | retired | unknown
Comments

A nominal state-transition diagram can be found in the Definition pattern documentation.

Unknown does not represent 'other' - one of the defined statuses must apply. Unknown is used when the authoring system is not sure what the current status is.

See guidance around (not) making local changes to elements here.

Control1..1
BindingThe codes SHALL be taken from PublicationStatus
(required to http://hl7.org/fhir/ValueSet/publication-status|5.0.0)

The lifecycle status of an artifact.

Typecode
Is Modifiertrue because This is labeled as "Is Modifier" because applications should not use a retired {{title}} without due consideration
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supportfalse
Summarytrue
Requirements

Enables tracking the life-cycle of the content and filtering of {{title}}s that are appropriate for use versus not.

Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
32. FeatureDefinition.experimental
Definition

A Boolean value to indicate that this {{title}} is authored for testing purposes (or education/evaluation/marketing) and is not intended for genuine usage.

ShortFor testing purposes, not real usage
Comments

Allows filtering of {{title}}s that are appropriate for use versus not.

Control0..1
Typeboolean
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supportfalse
Summarytrue
Requirements

Enables experimental content to be developed following the same lifecycle that would be used for a production-level {{title}}.

Meaning if MissingIf absent, this resource is treated as though it is not experimental.
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
34. FeatureDefinition.date
Definition

The date (and optionally time) when the {{title}} was last significantly changed. The date must change when the business version changes and it must change if the status code changes. In addition, it should change when the substantive content of the {{title}} changes.

ShortDate last changed
Comments

The date is often not tracked until the resource is published, but may be present on draft content. Note that this is not the same as the resource last-modified-date, since the resource may be a secondary representation of the {{title}}. Additional specific dates may be added as extensions or be found by consulting Provenances associated with past versions of the resource.

See guidance around (not) making local changes to elements here.

Control0..1
TypedateTime
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supportfalse
Summarytrue
Alternate NamesRevision Date
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
36. FeatureDefinition.publisher
Definition

The name of the organization or individual responsible for the release and ongoing maintenance of the {{title}}.

ShortName of the publisher/steward (organization or individual)
Comments

Usually an organization but may be an individual. The publisher (or steward) of the {{title}} is the organization or individual primarily responsible for the maintenance and upkeep of the {{title}}. This is not necessarily the same individual or organization that developed and initially authored the content. The publisher is the primary point of contact for questions or issues with the {{title}}. This item SHOULD be populated unless the information is available from context.

Control0..1
Typestring
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supportfalse
Summarytrue
Requirements

Helps establish the "authority/credibility" of the {{title}}. May also allow for contact.

Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
38. FeatureDefinition.contact
Definition

Contact details to assist a user in finding and communicating with the publisher.

ShortContact details for the publisher
Comments

May be a web site, an email address, a telephone number, etc.

See guidance around (not) making local changes to elements here.

Control0..*
TypeContactDetail
Is Modifierfalse
Must Supportfalse
Summarytrue
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
40. FeatureDefinition.description
Definition

A free text natural language description of the {{title}} from a consumer's perspective.

ShortNatural language description of the {{title}}
Comments

This description can be used to capture details such as comments about misuse, instructions for clinical use and interpretation, literature references, examples from the paper world, etc. It is not a rendering of the {{title}} as conveyed in the 'text' field of the resource itself. This item SHOULD be populated unless the information is available from context.

Control0..1
Typemarkdown
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supportfalse
Summaryfalse
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
42. FeatureDefinition.useContext
Definition

The content was developed with a focus and intent of supporting the contexts that are listed. These contexts may be general categories (gender, age, ...) or may be references to specific programs (insurance plans, studies, ...) and may be used to assist with indexing and searching for appropriate {{title}}s.

ShortThe context that the content is intended to support
Comments

When multiple useContexts are specified, there is no expectation that all or even any of the contexts apply.

Control0..*
TypeUsageContext
Is Modifierfalse
Must Supportfalse
Summarytrue
Requirements

Assist in searching for appropriate content.

Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
44. FeatureDefinition.jurisdiction
Definition

A legal or geographic region in which the {{title}} is intended to be used.

ShortIntended jurisdiction for {{title}} (if applicable)
Comments

It may be possible for the {{title}} to be used in jurisdictions other than those for which it was originally designed or intended.

DEPRECATION NOTE: For consistency, implementations are encouraged to migrate to using the new 'jurisdiction' code in the useContext element. (I.e. useContext.code indicating http://terminology.hl7.org/CodeSystem/usage-context-type#jurisdiction and useContext.valueCodeableConcept indicating the jurisdiction.)

Control0..*
BindingUnless not suitable, these codes SHALL be taken from JurisdictionValueSet
(extensible to http://hl7.org/fhir/ValueSet/jurisdiction)

Countries and regions within which this artifact is targeted for use.

TypeCodeableConcept
Is Modifierfalse
Must Supportfalse
Summarytrue
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
46. FeatureDefinition.purpose
Definition

Explanation of why this {{title}} is needed and why it has been designed as it has.

ShortWhy this {{title}} is defined
Comments

This element does not describe the usage of the {{title}}. Instead, it provides traceability of "why" the resource is either needed or "why" it is defined as it is. This may be used to point to source materials or specifications that drove the structure of this {{title}}.

Control0..1
Typemarkdown
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supportfalse
Summaryfalse
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
48. FeatureDefinition.copyright
Definition

A copyright statement relating to the {{title}} and/or its contents. Copyright statements are generally legal restrictions on the use and publishing of the {{title}}.

ShortUse and/or publishing restrictions
Comments

The short copyright declaration (e.g. (c) '2015+ xyz organization' should be sent in the copyrightLabel element.

Control0..1
Typemarkdown
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supportfalse
Summaryfalse
Requirements

Consumers must be able to determine any legal restrictions on the use of the {{title}} and/or its content.

Alternate NamesLicense, Restrictions
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
50. FeatureDefinition.copyrightLabel
Definition

A short string (<50 characters), suitable for inclusion in a page footer that identifies the copyright holder, effective period, and optionally whether rights are resctricted. (e.g. 'All rights reserved', 'Some rights reserved').

ShortCopyright holder and year(s)
Comments

The (c) symbol should NOT be included in this string. It will be added by software when rendering the notation. Full details about licensing, restrictions, warrantees, etc. goes in the more general 'copyright' element.

Control0..1
Typestring
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supportfalse
Summaryfalse
Requirements

Defines the content expected to be rendered in all representations of the artifact.

Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
52. FeatureDefinition.valueType
Definition

Features are very boolean: true or false for whether the application implements the feature, but the value associated with the feature might be a number, a string, or some kind of code

ShortType of value associated with the feature
Control1..1
BindingThe codes SHALL be taken from FHIRTypes
(required to http://hl7.org/fhir/ValueSet/data-types)
Typecode
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
54. FeatureDefinition.valueSet
Definition

If a value set is specified, the value of the data type must come from the value set, and the value type must be one of the bindeable types defined in the FHIR specification

ShortValueSet that controls what coded value are allowed
Control0..1
Typecanonical(ValueSet)
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
56. FeatureDefinition.context
Definition

The elements on which this feature can be defined. These URLs take the form or Canonica(StructureDefinition)#{element-id}, where The structure definition is a reference to a FHIR resource - usually CapabilityStatement of TerminologyCapabilities, and the element-id is a defined element within one of the resources. This is used to state where the feature applies. some features are defined on applications, but others apply to particular resources, or operations on resources, or particular code systems etc

ShortThe FHIR elements on which this feature can be defined
Control0..*
Typeurl
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
58. FeatureDefinition.qualifier
Definition

A qualifier is an extra piece of information that MAY or SHALL be provided when the feature is described/specified that provides additional information about the feature. E.g. a feature defined on a resource may only be applicable to particular events associated with the resource, or ...?

ShortA qualifier that might provided more information about a feature implementation
Control0..*
TypeBackboneElement
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
60. FeatureDefinition.qualifier.id
Definition

Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.

ShortUnique id for inter-element referencing
Control0..1
This element is affected by the following invariants: ele-1
Typeid
Is Modifierfalse
XML FormatIn the XML format, this property is represented as an attribute.
Summaryfalse
62. FeatureDefinition.qualifier.extension
Definition

May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and managable, 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.

ShortAdditional content defined by implementations
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.

Control0..*
TypeExtension
Is Modifierfalse
Summaryfalse
Alternate Namesextensions, user content
Invariantsele-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())
SlicingThis element introduces a set of slices on FeatureDefinition.qualifier.extension. The slices areUnordered and Open, and can be differentiated using the following discriminators:
  • value @ url
  • 64. FeatureDefinition.qualifier.modifierExtension
    Definition

    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 in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and managable, 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. Applications processing a resource are required to check for modifier extensions.

    Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself).

    ShortExtensions that cannot be ignored even if unrecognized
    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.

    Control0..*
    TypeExtension
    Is Modifiertrue because Modifier extensions are expected to modify the meaning or interpretation of the element that contains them
    Summarytrue
    Requirements

    Modifier extensions allow for extensions that cannot be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the definition of modifier extensions.

    Alternate Namesextensions, user content, modifiers
    Invariantsele-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())
    66. FeatureDefinition.qualifier.name
    Definition

    The name of the feature

    ShortThe name of the feature
    Control1..1
    Typecode
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    68. FeatureDefinition.qualifier.description
    Definition

    A human-readable description of the qualifier.

    ShortA human-readable description of the qualifier.
    Control0..1
    Typestring
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    70. FeatureDefinition.qualifier.valueType
    Definition

    Features are very boolean: true or false for whether the application implements the feature, but the value associated with the feature might be a number, a string, or some kind of code

    ShortType of value associated with the feature
    Control1..1
    BindingThe codes SHALL be taken from FHIRTypes
    (required to http://hl7.org/fhir/ValueSet/data-types)
    Typecode
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    72. FeatureDefinition.qualifier.optional
    Definition

    Whether the feature is optional, or must always be present when a feature is referred to

    ShortWhether the feature is optional, or must always be present
    Control1..1
    Typeboolean
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension