Canonical Resource Management Infrastructure Implementation Guide
1.0.0 - STU1 International flag

This page is part of the Canonical Resource Management Infrastructure Implementation Guide (v1.0.0: STU1) based on FHIR (HL7® FHIR® Standard) R4. This is the current published version. For a full list of available versions, see the Directory of published versions

Resource Profile: CRMIShareableCodeSystem - Detailed Descriptions

Page standards status: Trial-use Maturity Level: 4

Definitions for the crmi-shareablecodesystem resource profile.

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

0. CodeSystem
Control1..1
Invariantsscs-1: If a codesystem contains nested concepts, it must specify hierarchyMeaning (concept.concept.exists() implies hierarchyMeaning.exists())
scs-2: If a codesystem contains example, fragment, or complete content, it must have at least one concept (content in ( 'example' | 'fragment' | 'complete' ) implies concept.exists())
2. CodeSystem.extension:knowledgeCapability
Slice NameknowledgeCapability
Control0..*
TypeExtension(CQF Knowledge capability) (Extension Type: code)
Must Supporttrue
4. CodeSystem.extension:versionAlgorithm
Slice NameversionAlgorithm
Control0..1
TypeExtension(Artifact Version Algorithm) (Extension Type: Choice of: string, Coding)
Must Supporttrue
6. CodeSystem.extension:versionPolicy
Slice NameversionPolicy
Control0..1
TypeExtension(Artifact Version Policy) (Extension Type: CodeableConcept)
Must Supporttrue
8. CodeSystem.url
Control1..1
Must Supporttrue
10. CodeSystem.version
NoteThis is a business version Id, not a resource version Id (see discussion)
Control1..1
Typestring
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supporttrue
12. CodeSystem.name
Must Supporttrue
14. CodeSystem.title
Control1..1
Must Supporttrue
16. CodeSystem.status
Must Supporttrue
18. CodeSystem.experimental
Control1..1
Must Supporttrue
20. CodeSystem.publisher
Must Supporttrue
22. CodeSystem.description
Control1..1
Must Supporttrue
24. CodeSystem.caseSensitive
Control1..1
Must Supporttrue
26. CodeSystem.hierarchyMeaning
Must Supporttrue
28. CodeSystem.content
Must Supporttrue
30. CodeSystem.concept
Must Supporttrue
32. CodeSystem.concept.code
Control1..1
Must Supporttrue
34. CodeSystem.concept.display
Must Supporttrue
36. CodeSystem.concept.definition
Must Supporttrue
38. CodeSystem.concept.concept
Control0..*
This element is affected by the following invariants: scs-1
TypeSeettp://hl7.org/fhir/StructureDefinition/CodeSystem#CodeSystem.concept
Must Supporttrue

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

0. CodeSystem
Definition

The CodeSystem resource is used to declare the existence of and describe a code system or code system supplement and its key properties, and optionally define a part or all of its content.

ShortDeclares the existence of and describes a code system or code system supplement
Control10..1*
Is Modifierfalse
Summaryfalse
Invariantscsd-0: Name should be usable as an identifier for the module by machine processing applications such as code generation (name.matches('[A-Z]([A-Za-z0-9_]){0,254}'))
csd-1: Within a code system definition, all the codes SHALL be unique (concept.code.combine($this.descendants().concept.code).isDistinct())
dom-2: If the resource is contained in another resource, it SHALL NOT contain nested Resources (contained.contained.empty())
dom-3: If the resource is contained in another resource, it SHALL be referred to from elsewhere in the resource or SHALL refer to the containing resource (contained.where((('#'+id in (%resource.descendants().reference | %resource.descendants().as(canonical) | %resource.descendants().as(uri) | %resource.descendants().as(url))) or descendants().where(reference = '#').exists() or descendants().where(as(canonical) = '#').exists() or descendants().where(as(canonical) = '#').exists()).not()).trace('unmatched', id).empty())
dom-4: If a resource is contained in another resource, it SHALL NOT have a meta.versionId or a meta.lastUpdated (contained.meta.versionId.empty() and contained.meta.lastUpdated.empty())
dom-5: If a resource is contained in another resource, it SHALL NOT have a security label (contained.meta.security.empty())
dom-6: A resource should have narrative for robust management (text.`div`.exists())
scs-1: If a codesystem contains nested concepts, it must specify hierarchyMeaning (concept.concept.exists() implies hierarchyMeaning.exists())
scs-2: If a codesystem contains example, fragment, or complete content, it must have at least one concept (content in ( 'example' | 'fragment' | 'complete' ) implies concept.exists())
csd-0: Name should be usable as an identifier for the module by machine processing applications such as code generation (name.matches('[A-Z]([A-Za-z0-9_]){0,254}'))
csd-1: Within a code system definition, all the codes SHALL be unique (concept.code.combine($this.descendants().concept.code).isDistinct())
2. CodeSystem.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 it's 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 it's meaning or interpretation
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Summarytrue
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
4. CodeSystem.extension:knowledgeCapability
Slice NameknowledgeCapability
Definition

Defines a knowledge capability afforded by this knowledge artifact.

Shortshareable | computable | publishable | executable
Control0..*
TypeExtension(CQF Knowledge capability) (Extension Type: code)
Is Modifierfalse
Must Supporttrue
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())
ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
6. CodeSystem.extension:versionAlgorithm
Slice NameversionAlgorithm
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
TypeExtension(Artifact Version Algorithm) (Extension Type: Choice of: string, Coding)
Is Modifierfalse
Must Supporttrue
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())
ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
8. CodeSystem.extension:versionPolicy
Slice NameversionPolicy
Definition

Defines the versioning policy of the artifact.

Shortmetadata | strict
Control0..1
TypeExtension(Artifact Version Policy) (Extension Type: CodeableConcept)
Is Modifierfalse
Must Supporttrue
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())
ele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
ext-1: Must have either extensions or value[x], not both (extension.exists() != value.exists())
10. CodeSystem.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 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.

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
Summaryfalse
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())
12. CodeSystem.url
Definition

An absolute URI that is used to identify this code system 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 at which an authoritative instance of this code system is (or will be) published. This URL can be the target of a canonical reference. It SHALL remain the same when the code system is stored on different servers. This is used in Coding.system.

ShortCanonical identifier for this code system, represented as a URI (globally unique) (Coding.system)
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.

Control10..1
Typeuri
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supporttrue
Summarytrue
Requirements

Allows the code system to be referenced by a single globally unique identifier.

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

The identifier that is used to identify this version of the code system when it is referenced in a specification, model, design or instance. This is an arbitrary value managed by the code system 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. This is used in Coding.version.

ShortBusiness version of the code system (Coding.version)
Comments

There may be different code system instances that have the same identifier 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 code system with the format [url]|[version].

NoteThis is a business version Id, not a resource version Id (see discussion)
Control10..1
Typestring
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supporttrue
Summarytrue
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
16. CodeSystem.name
Definition

A natural language name identifying the code system. This name should be usable as an identifier for the module by machine processing applications such as code generation.

ShortName for this code system (computer friendly)
Comments

The name is not expected to be globally unique. The name should be a simple alphanumeric type name to ensure that it is machine-processing friendly.

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

Support human navigation and code generation.

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

A short, descriptive, user-friendly title for the code system.

ShortName for this code system (human friendly)
Comments

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

Control10..1
Typestring
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supporttrue
Summarytrue
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
20. CodeSystem.status
Definition

The date (and optionally time) when the code system resource was created or revised.

Shortdraft | active | retired | unknown
Comments

Allows filtering of code systems that are appropriate for use versus not.

Control1..1
BindingThe codes SHALL be taken from PublicationStatushttp://hl7.org/fhir/ValueSet/publication-status|4.0.1
(required to http://hl7.org/fhir/ValueSet/publication-status|4.0.1)

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 Supporttrue
Summarytrue
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
22. CodeSystem.experimental
Definition

A Boolean value to indicate that this code system is authored for testing purposes (or education/evaluation/marketing) and is not intended to be used for genuine usage.

ShortFor testing purposes, not real usage
Comments

Allows filtering of code systems that are appropriate for use versus not.

Control10..1
Typeboolean
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supporttrue
Summarytrue
Requirements

Enables experimental content to be developed following the same lifecycle that would be used for a production-level code system.

Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
24. CodeSystem.publisher
Definition

The name of the organization or individual that published the code system.

ShortName of the publisher (organization or individual)
Comments

Usually an organization but may be an individual. The publisher (or steward) of the code system is the organization or individual primarily responsible for the maintenance and upkeep of the code system. 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 code system. 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 Supporttrue
Summarytrue
Requirements

Helps establish the "authority/credibility" of the code system. May also allow for contact.

Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
26. CodeSystem.description
Definition

A free text natural language description of the code system from a consumer's perspective.

ShortNatural language description of the code system
Comments

This description can be used to capture details such as why the code system was built, comments about misuse, instructions for clinical use and interpretation, literature references, examples from the paper world, etc. It is not a rendering of the code system as conveyed in the 'text' field of the resource itself. This item SHOULD be populated unless the information is available from context (e.g. the language of the code system is presumed to be the predominant language in the place the code system was created).

Control10..1
Typemarkdown
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supporttrue
Summaryfalse
Alternate NamesScope, Purpose
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
28. CodeSystem.caseSensitive
Definition

If code comparison is case sensitive when codes within this system are compared to each other.

ShortIf code comparison is case sensitive
Comments

If this value is missing, then it is not specified whether a code system is case sensitive or not. When the rule is not known, Postel's law should be followed: produce codes with the correct case, and accept codes in any case. This element is primarily provided to support validation software.

Control10..1
Typeboolean
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supporttrue
Summarytrue
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
30. CodeSystem.hierarchyMeaning
Definition

The meaning of the hierarchy of concepts as represented in this resource.

Shortgrouped-by | is-a | part-of | classified-with
Comments

Note that other representations might have a different hierarchy or none at all, and represent the information using properties.

Control0..1
This element is affected by the following invariants: scs-1
BindingThe codes SHALL be taken from CodeSystemHierarchyMeaninghttp://hl7.org/fhir/ValueSet/codesystem-hierarchy-meaning|4.0.1
(required to http://hl7.org/fhir/ValueSet/codesystem-hierarchy-meaning|4.0.1)

The meaning of the hierarchy of concepts in a code system.

Typecode
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supporttrue
Summarytrue
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
32. CodeSystem.content
Definition

The extent of the content of the code system (the concepts and codes it defines) are represented in this resource instance.

Shortnot-present | example | fragment | complete | supplement
Control1..1
This element is affected by the following invariants: scs-2
BindingThe codes SHALL be taken from CodeSystemContentModehttp://hl7.org/fhir/ValueSet/codesystem-content-mode|4.0.1
(required to http://hl7.org/fhir/ValueSet/codesystem-content-mode|4.0.1)

The extent of the content of the code system (the concepts and codes it defines) are represented in a code system resource.

Typecode
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supporttrue
Summarytrue
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
34. CodeSystem.concept
Definition

Concepts that are in the code system. The concept definitions are inherently hierarchical, but the definitions must be consulted to determine what the meanings of the hierarchical relationships are.

ShortConcepts in the code system
Comments

If this is empty, it means that the code system resource does not represent the content of the code system.

Control0..*
This element is affected by the following invariants: scs-2
TypeBackboneElement
Is Modifierfalse
Must Supporttrue
Summaryfalse
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
36. CodeSystem.concept.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 manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. 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())
38. CodeSystem.concept.code
Definition

A code - a text symbol - that uniquely identifies the concept within the code system.

ShortCode that identifies concept
Control1..1
Typecode
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supporttrue
Summaryfalse
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
40. CodeSystem.concept.display
Definition

A human readable string that is the recommended default way to present this concept to a user.

ShortText to display to the user
Control0..1
Typestring
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supporttrue
Summaryfalse
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
42. CodeSystem.concept.definition
Definition

The formal definition of the concept. The code system resource does not make formal definitions required, because of the prevalence of legacy systems. However, they are highly recommended, as without them there is no formal meaning associated with the concept.

ShortFormal definition
Control0..1
Typestring
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Must Supporttrue
Summaryfalse
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
44. CodeSystem.concept.concept
Definition

Defines children of a concept to produce a hierarchy of concepts. The nature of the relationships is variable (is-a/contains/categorizes) - see hierarchyMeaning.

ShortChild Concepts (is-a/contains/categorizes)
Control0..*
This element is affected by the following invariants: scs-1
TypeSeettp://hl7.org/fhir/StructureDefinition/CodeSystem#CodeSystem.concept
Is Modifierfalse
Must Supporttrue
Summaryfalse
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))

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

0. CodeSystem
Definition

The CodeSystem resource is used to declare the existence of and describe a code system or code system supplement and its key properties, and optionally define a part or all of its content.

ShortDeclares the existence of and describes a code system or code system supplement
Control1..1
Is Modifierfalse
Summaryfalse
Invariantscsd-0: Name should be usable as an identifier for the module by machine processing applications such as code generation (name.matches('[A-Z]([A-Za-z0-9_]){0,254}'))
csd-1: Within a code system definition, all the codes SHALL be unique (concept.code.combine($this.descendants().concept.code).isDistinct())
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().as(canonical) | %resource.descendants().as(uri) | %resource.descendants().as(url))) or descendants().where(reference = '#').exists() or descendants().where(as(canonical) = '#').exists() or descendants().where(as(canonical) = '#').exists()).not()).trace('unmatched', id).empty())
dom-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())
scs-1: If a codesystem contains nested concepts, it must specify hierarchyMeaning (concept.concept.exists() implies hierarchyMeaning.exists())
scs-2: If a codesystem contains example, fragment, or complete content, it must have at least one concept (content in ( 'example' | 'fragment' | 'complete' ) implies concept.exists())
2. CodeSystem.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

The only time that a resource does not have an id is when it is being submitted to the server using a create operation.

Control0..1
Typeid
Is Modifierfalse
Summarytrue
4. CodeSystem.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
Summarytrue
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
6. CodeSystem.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 it's 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 it's meaning or interpretation
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Summarytrue
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
8. CodeSystem.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 SHOULD be taken from CommonLanguages
(preferred to http://hl7.org/fhir/ValueSet/languages)

A human language.

Additional BindingsPurpose
AllLanguagesMax Binding
Typecode
Is Modifierfalse
Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
Summaryfalse
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
10. CodeSystem.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 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
TypeNarrative
Is Modifierfalse
Summaryfalse
Alternate Namesnarrative, html, xhtml, display
Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
12. CodeSystem.contained
Definition

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.

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..*
TypeResource
Is Modifierfalse
Summaryfalse
Alternate Namesinline resources, anonymous resources, contained resources
14. CodeSystem.extension
Definition

An Extension

ShortExtension
Control0..*
TypeExtension
Is Modifierfalse
Summaryfalse
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 CodeSystem.extension. The slices areUnordered and Open, and can be differentiated using the following discriminators:
  • value @ url
  • 16. CodeSystem.extension:knowledgeCapability
    Slice NameknowledgeCapability
    Definition

    Defines a knowledge capability afforded by this knowledge artifact.

    Shortshareable | computable | publishable | executable
    Control0..*
    TypeExtension(CQF Knowledge capability) (Extension Type: code)
    Is Modifierfalse
    Must Supporttrue
    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. CodeSystem.extension:versionAlgorithm
    Slice NameversionAlgorithm
    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
    TypeExtension(Artifact Version Algorithm) (Extension Type: Choice of: string, Coding)
    Is Modifierfalse
    Must Supporttrue
    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. CodeSystem.extension:versionPolicy
    Slice NameversionPolicy
    Definition

    Defines the versioning policy of the artifact.

    Shortmetadata | strict
    Control0..1
    TypeExtension(Artifact Version Policy) (Extension Type: CodeableConcept)
    Is Modifierfalse
    Must Supporttrue
    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())
    22. CodeSystem.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 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.

    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
    Summaryfalse
    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())
    24. CodeSystem.url
    Definition

    An absolute URI that is used to identify this code system 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 at which an authoritative instance of this code system is (or will be) published. This URL can be the target of a canonical reference. It SHALL remain the same when the code system is stored on different servers. This is used in Coding.system.

    ShortCanonical identifier for this code system, represented as a URI (globally unique) (Coding.system)
    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.

    Control1..1
    Typeuri
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Must Supporttrue
    Summarytrue
    Requirements

    Allows the code system to be referenced by a single globally unique identifier.

    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    26. CodeSystem.identifier
    Definition

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

    ShortAdditional identifier for the code system (business identifier)
    Comments

    Typically, this is used for identifiers that can go in an HL7 V3 II (instance identifier) data type, and can then identify this code system outside of FHIR, where it is not possible to use the logical URI. Note that HL7 defines at least three identifiers for many of its code systems - the FHIR canonical URL, the OID and the V2 Table 0396 mnemonic code.

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

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

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

    The identifier that is used to identify this version of the code system when it is referenced in a specification, model, design or instance. This is an arbitrary value managed by the code system 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. This is used in Coding.version.

    ShortBusiness version of the code system (Coding.version)
    Comments

    There may be different code system instances that have the same identifier 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 code system with the format [url]|[version].

    NoteThis is a business version Id, not a resource version Id (see discussion)
    Control1..1
    Typestring
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Must Supporttrue
    Summarytrue
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    30. CodeSystem.name
    Definition

    A natural language name identifying the code system. This name should be usable as an identifier for the module by machine processing applications such as code generation.

    ShortName for this code system (computer friendly)
    Comments

    The name is not expected to be globally unique. The name should be a simple alphanumeric type name to ensure that it is machine-processing friendly.

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

    Support human navigation and code generation.

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

    A short, descriptive, user-friendly title for the code system.

    ShortName for this code system (human friendly)
    Comments

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

    Control1..1
    Typestring
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Must Supporttrue
    Summarytrue
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    34. CodeSystem.status
    Definition

    The date (and optionally time) when the code system resource was created or revised.

    Shortdraft | active | retired | unknown
    Comments

    Allows filtering of code systems that are appropriate for use versus not.

    Control1..1
    BindingThe codes SHALL be taken from PublicationStatus
    (required to http://hl7.org/fhir/ValueSet/publication-status|4.0.1)

    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 Supporttrue
    Summarytrue
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    36. CodeSystem.experimental
    Definition

    A Boolean value to indicate that this code system is authored for testing purposes (or education/evaluation/marketing) and is not intended to be used for genuine usage.

    ShortFor testing purposes, not real usage
    Comments

    Allows filtering of code systems that are appropriate for use versus not.

    Control1..1
    Typeboolean
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Must Supporttrue
    Summarytrue
    Requirements

    Enables experimental content to be developed following the same lifecycle that would be used for a production-level code system.

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

    The date (and optionally time) when the code system was published. 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 code system changes.

    ShortDate last changed
    Comments

    Note that this is not the same as the resource last-modified-date, since the resource may be a secondary representation of the code system. Additional specific dates may be added as extensions or be found by consulting Provenances associated with past versions of the resource.

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

    The name of the organization or individual that published the code system.

    ShortName of the publisher (organization or individual)
    Comments

    Usually an organization but may be an individual. The publisher (or steward) of the code system is the organization or individual primarily responsible for the maintenance and upkeep of the code system. 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 code system. 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 Supporttrue
    Summarytrue
    Requirements

    Helps establish the "authority/credibility" of the code system. May also allow for contact.

    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    42. CodeSystem.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.

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

    A free text natural language description of the code system from a consumer's perspective.

    ShortNatural language description of the code system
    Comments

    This description can be used to capture details such as why the code system was built, comments about misuse, instructions for clinical use and interpretation, literature references, examples from the paper world, etc. It is not a rendering of the code system as conveyed in the 'text' field of the resource itself. This item SHOULD be populated unless the information is available from context (e.g. the language of the code system is presumed to be the predominant language in the place the code system was created).

    Control1..1
    Typemarkdown
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Must Supporttrue
    Summaryfalse
    Alternate NamesScope, Purpose
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    46. CodeSystem.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 code system instances.

    ShortThe context that the content is intended to support
    Comments

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

    Control0..*
    TypeUsageContext
    Is Modifierfalse
    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()))
    48. CodeSystem.jurisdiction
    Definition

    A legal or geographic region in which the code system is intended to be used.

    ShortIntended jurisdiction for code system (if applicable)
    Comments

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

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

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

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

    Explanation of why this code system is needed and why it has been designed as it has.

    ShortWhy this code system is defined
    Comments

    This element does not describe the usage of the code system. 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 code system.

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

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

    ShortUse and/or publishing restrictions
    Comments

    ... Sometimes, the copyright differs between the code system and the codes that are included. The copyright statement should clearly differentiate between these when required.

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

    Consumers must be able to determine any legal restrictions on the use of the code system and/or its content.

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

    If code comparison is case sensitive when codes within this system are compared to each other.

    ShortIf code comparison is case sensitive
    Comments

    If this value is missing, then it is not specified whether a code system is case sensitive or not. When the rule is not known, Postel's law should be followed: produce codes with the correct case, and accept codes in any case. This element is primarily provided to support validation software.

    Control1..1
    Typeboolean
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Must Supporttrue
    Summarytrue
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    56. CodeSystem.valueSet
    Definition

    Canonical reference to the value set that contains the entire code system.

    ShortCanonical reference to the value set with entire code system
    Comments

    The definition of the value set SHALL include all codes from this code system and only codes from this code system, and it SHALL be immutable.

    Control0..1
    Typecanonical(ValueSet)
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Summarytrue
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    58. CodeSystem.hierarchyMeaning
    Definition

    The meaning of the hierarchy of concepts as represented in this resource.

    Shortgrouped-by | is-a | part-of | classified-with
    Comments

    Note that other representations might have a different hierarchy or none at all, and represent the information using properties.

    Control0..1
    This element is affected by the following invariants: scs-1
    BindingThe codes SHALL be taken from CodeSystemHierarchyMeaning
    (required to http://hl7.org/fhir/ValueSet/codesystem-hierarchy-meaning|4.0.1)

    The meaning of the hierarchy of concepts in a code system.

    Typecode
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Must Supporttrue
    Summarytrue
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    60. CodeSystem.compositional
    Definition

    The code system defines a compositional (post-coordination) grammar.

    ShortIf code system defines a compositional grammar
    Comments

    Note that the code system resource does not define what the compositional grammar is, only whether or not there is one.

    Control0..1
    Typeboolean
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Summarytrue
    Alternate Namesgrammar
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    62. CodeSystem.versionNeeded
    Definition

    This flag is used to signify that the code system does not commit to concept permanence across versions. If true, a version must be specified when referencing this code system.

    ShortIf definitions are not stable
    Comments

    Best practice is that code systems do not redefine concepts, or that if concepts are redefined, a new code system definition is created. But this is not always possible, so some code systems may be defined as 'versionNeeded'.

    Most code systems occasionally refine the displays defined for concepts between versions. Contexts in which the concept display values are validated may require that the version be specified for some code systems irrespective of the value of this property.

    Control0..1
    Typeboolean
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Summarytrue
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    64. CodeSystem.content
    Definition

    The extent of the content of the code system (the concepts and codes it defines) are represented in this resource instance.

    Shortnot-present | example | fragment | complete | supplement
    Control1..1
    This element is affected by the following invariants: scs-2
    BindingThe codes SHALL be taken from CodeSystemContentMode
    (required to http://hl7.org/fhir/ValueSet/codesystem-content-mode|4.0.1)

    The extent of the content of the code system (the concepts and codes it defines) are represented in a code system resource.

    Typecode
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Must Supporttrue
    Summarytrue
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    66. CodeSystem.supplements
    Definition

    The canonical URL of the code system that this code system supplement is adding designations and properties to.

    ShortCanonical URL of Code System this adds designations and properties to
    Comments

    The most common use of a code system supplement is to add additional language support.

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

    The total number of concepts defined by the code system. Where the code system has a compositional grammar, the basis of this count is defined by the system steward.

    ShortTotal concepts in the code system
    Comments

    The count of concepts defined in this resource cannot be more than this value but may be less for several reasons - see the content element.

    Control0..1
    TypeunsignedInt
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Summarytrue
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    70. CodeSystem.filter
    Definition

    A filter that can be used in a value set compose statement when selecting concepts using a filter.

    ShortFilter that can be used in a value set
    Comments

    Note that filters defined in code systems usually require custom code on the part of any terminology engine that will make them available for use in value set filters. For this reason, they are generally only seen in high value published terminologies.

    Control0..*
    TypeBackboneElement
    Is Modifierfalse
    Summarytrue
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    72. CodeSystem.filter.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
    Typestring
    Is Modifierfalse
    XML FormatIn the XML format, this property is represented as an attribute.
    Summaryfalse
    74. CodeSystem.filter.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 manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

    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())
    76. CodeSystem.filter.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 manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. 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())
    78. CodeSystem.filter.code
    Definition

    The code that identifies this filter when it is used as a filter in ValueSet.compose.include.filter.

    ShortCode that identifies the filter
    Control1..1
    Typecode
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Summarytrue
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    80. CodeSystem.filter.description
    Definition

    A description of how or why the filter is used.

    ShortHow or why the filter is used
    Control0..1
    Typestring
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Summarytrue
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    82. CodeSystem.filter.operator
    Definition

    A list of operators that can be used with the filter.

    Short= | is-a | descendent-of | is-not-a | regex | in | not-in | generalizes | exists
    Control1..*
    BindingThe codes SHALL be taken from FilterOperator
    (required to http://hl7.org/fhir/ValueSet/filter-operator|4.0.1)

    The kind of operation to perform as a part of a property based filter.

    Typecode
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Summarytrue
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    84. CodeSystem.filter.value
    Definition

    A description of what the value for the filter should be.

    ShortWhat to use for the value
    Control1..1
    Typestring
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Summarytrue
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    86. CodeSystem.property
    Definition

    A property defines an additional slot through which additional information can be provided about a concept.

    ShortAdditional information supplied about each concept
    Control0..*
    TypeBackboneElement
    Is Modifierfalse
    Summarytrue
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    88. CodeSystem.property.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
    Typestring
    Is Modifierfalse
    XML FormatIn the XML format, this property is represented as an attribute.
    Summaryfalse
    90. CodeSystem.property.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 manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

    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())
    92. CodeSystem.property.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 manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. 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())
    94. CodeSystem.property.code
    Definition

    A code that is used to identify the property. The code is used internally (in CodeSystem.concept.property.code) and also externally, such as in property filters.

    ShortIdentifies the property on the concepts, and when referred to in operations
    Control1..1
    Typecode
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Summarytrue
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    96. CodeSystem.property.uri
    Definition

    Reference to the formal meaning of the property. One possible source of meaning is the Concept Properties code system.

    ShortFormal identifier for the property
    Control0..1
    Typeuri
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Summarytrue
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    98. CodeSystem.property.description
    Definition

    A description of the property- why it is defined, and how its value might be used.

    ShortWhy the property is defined, and/or what it conveys
    Control0..1
    Typestring
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Summarytrue
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    100. CodeSystem.property.type
    Definition

    The type of the property value. Properties of type "code" contain a code defined by the code system (e.g. a reference to another defined concept).

    Shortcode | Coding | string | integer | boolean | dateTime | decimal
    Control1..1
    BindingThe codes SHALL be taken from PropertyType
    (required to http://hl7.org/fhir/ValueSet/concept-property-type|4.0.1)

    The type of a property value.

    Typecode
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Summarytrue
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    102. CodeSystem.concept
    Definition

    Concepts that are in the code system. The concept definitions are inherently hierarchical, but the definitions must be consulted to determine what the meanings of the hierarchical relationships are.

    ShortConcepts in the code system
    Comments

    If this is empty, it means that the code system resource does not represent the content of the code system.

    Control0..*
    This element is affected by the following invariants: scs-2
    TypeBackboneElement
    Is Modifierfalse
    Must Supporttrue
    Summaryfalse
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    104. CodeSystem.concept.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
    Typestring
    Is Modifierfalse
    XML FormatIn the XML format, this property is represented as an attribute.
    Summaryfalse
    106. CodeSystem.concept.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 manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

    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())
    108. CodeSystem.concept.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 manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. 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())
    110. CodeSystem.concept.code
    Definition

    A code - a text symbol - that uniquely identifies the concept within the code system.

    ShortCode that identifies concept
    Control1..1
    Typecode
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Must Supporttrue
    Summaryfalse
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    112. CodeSystem.concept.display
    Definition

    A human readable string that is the recommended default way to present this concept to a user.

    ShortText to display to the user
    Control0..1
    Typestring
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Must Supporttrue
    Summaryfalse
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    114. CodeSystem.concept.definition
    Definition

    The formal definition of the concept. The code system resource does not make formal definitions required, because of the prevalence of legacy systems. However, they are highly recommended, as without them there is no formal meaning associated with the concept.

    ShortFormal definition
    Control0..1
    Typestring
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Must Supporttrue
    Summaryfalse
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    116. CodeSystem.concept.designation
    Definition

    Additional representations for the concept - other languages, aliases, specialized purposes, used for particular purposes, etc.

    ShortAdditional representations for the concept
    Comments

    Concepts have both a display and an array of designation. The display is equivalent to a special designation with an implied designation.use of "primary code" and a language equal to the Resource Language.

    Control0..*
    TypeBackboneElement
    Is Modifierfalse
    Summaryfalse
    Requirements

    Many concept definition systems support multiple representations, in multiple languages, and for multiple purposes.

    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    118. CodeSystem.concept.designation.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
    Typestring
    Is Modifierfalse
    XML FormatIn the XML format, this property is represented as an attribute.
    Summaryfalse
    120. CodeSystem.concept.designation.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 manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

    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())
    122. CodeSystem.concept.designation.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 manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. 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())
    124. CodeSystem.concept.designation.language
    Definition

    The language this designation is defined for.

    ShortHuman language of the designation
    Comments

    In the absence of a language, the resource language applies.

    Control0..1
    BindingThe codes SHOULD be taken from CommonLanguages
    (preferred to http://hl7.org/fhir/ValueSet/languages)

    A human language.

    Additional BindingsPurpose
    AllLanguagesMax Binding
    Typecode
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Summaryfalse
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    126. CodeSystem.concept.designation.use
    Definition

    A code that details how this designation would be used.

    ShortDetails how this designation would be used
    Comments

    If no use is provided, the designation can be assumed to be suitable for general display to a human user.

    Control0..1
    BindingUnless not suitable, these codes SHALL be taken from DesignationUse
    (extensible to http://hl7.org/fhir/ValueSet/designation-use)

    Details of how a designation would be used.

    TypeCoding
    Is Modifierfalse
    Summaryfalse
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    128. CodeSystem.concept.designation.value
    Definition

    The text value for this designation.

    ShortThe text value for this designation
    Control1..1
    Typestring
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Summaryfalse
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    130. CodeSystem.concept.property
    Definition

    A property value for this concept.

    ShortProperty value for the concept
    Control0..*
    TypeBackboneElement
    Is Modifierfalse
    Summaryfalse
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    132. CodeSystem.concept.property.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
    Typestring
    Is Modifierfalse
    XML FormatIn the XML format, this property is represented as an attribute.
    Summaryfalse
    134. CodeSystem.concept.property.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 manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.

    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())
    136. CodeSystem.concept.property.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 manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. 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())
    138. CodeSystem.concept.property.code
    Definition

    A code that is a reference to CodeSystem.property.code.

    ShortReference to CodeSystem.property.code
    Control1..1
    Typecode
    Is Modifierfalse
    Primitive ValueThis primitive element may be present, or absent, or replaced by an extension
    Summaryfalse
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    140. CodeSystem.concept.property.value[x]
    Definition

    The value of this property.

    ShortValue of the property for this concept
    Control1..1
    TypeChoice of: code, Coding, string, integer, boolean, dateTime, decimal
    [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
    Summaryfalse
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))
    142. CodeSystem.concept.concept
    Definition

    Defines children of a concept to produce a hierarchy of concepts. The nature of the relationships is variable (is-a/contains/categorizes) - see hierarchyMeaning.

    ShortChild Concepts (is-a/contains/categorizes)
    Control0..*
    This element is affected by the following invariants: scs-1
    TypeSeettp://hl7.org/fhir/StructureDefinition/CodeSystem#CodeSystem.concept
    Is Modifierfalse
    Must Supporttrue
    Summaryfalse
    Invariantsele-1: All FHIR elements must have a @value or children (hasValue() or (children().count() > id.count()))