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Vocabulary Work GroupMaturity Level: 5 Normative Compartments: Not linked to any defined compartments

Detailed Descriptions for the elements in the CodeSystem resource.

CodeSystem
Element IdCodeSystem
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.

Control1..1
TypeDomainResource
Invariants
Defined on this element
csd-0Warning Name should be usable as an identifier for the module by machine processing applications such as code generationname.matches('[A-Z]([A-Za-z0-9_]){0,254}')
csd-1Rule Within a code system definition, all the codes SHALL be uniqueconcept.code.combine($this.descendants().concept.code).isDistinct()
CodeSystem.url
Element IdCodeSystem.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.

Control0..1
Typeuri
Requirements

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

Summarytrue
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.

CodeSystem.identifier
Element IdCodeSystem.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.

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

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

Summarytrue
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.

CodeSystem.version
Element IdCodeSystem.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.

NoteThis is a business versionId, not a resource version id (see discussion)
Control0..1
Typestring
Summarytrue
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].

CodeSystem.name
Element IdCodeSystem.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.

Control0..1
Typestring
Requirements

Support human navigation and code generation.

Summarytrue
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.

Invariants
Affect this element
inv-0Warning Name should be usable as an identifier for the module by machine processing applications such as code generationname.matches('[A-Z]([A-Za-z0-9_]){0,254}')
CodeSystem.title
Element IdCodeSystem.title
Definition

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

Control0..1
Typestring
Summarytrue
Comments

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

CodeSystem.status
Element IdCodeSystem.status
Definition

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

Control1..1
Terminology BindingPublicationStatus (Required)
Typecode
Is Modifiertrue (Reason: This is labeled as "Is Modifier" because applications should not use a retired {{title}} without due consideration)
Summarytrue
Comments

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

CodeSystem.experimental
Element IdCodeSystem.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.

Control0..1
Typeboolean
Requirements

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

Summarytrue
Comments

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

CodeSystem.date
Element IdCodeSystem.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.

Control0..1
TypedateTime
Alternate NamesRevision Date
Summarytrue
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.

CodeSystem.publisher
Element IdCodeSystem.publisher
Definition

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

Control0..1
Typestring
Requirements

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

Summarytrue
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.

CodeSystem.contact
Element IdCodeSystem.contact
Definition

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

Control0..*
TypeContactDetail
Summarytrue
Comments

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

CodeSystem.description
Element IdCodeSystem.description
Definition

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

Control0..1
Typemarkdown
Alternate NamesScope; Purpose
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).

CodeSystem.useContext
Element IdCodeSystem.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.

Control0..*
TypeUsageContext
Requirements

Assist in searching for appropriate content.

Summarytrue
Comments

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

CodeSystem.jurisdiction
Element IdCodeSystem.jurisdiction
Definition

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

Control0..*
Terminology BindingJurisdiction (Extensible)
TypeCodeableConcept
Summarytrue
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.

CodeSystem.purpose
Element IdCodeSystem.purpose
Definition

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

Control0..1
Typemarkdown
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.

CodeSystem.copyright
Element IdCodeSystem.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.

Control0..1
Typemarkdown
Requirements

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

Alternate NamesLicense; 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.

CodeSystem.caseSensitive
Element IdCodeSystem.caseSensitive
Definition

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

Control0..1
Typeboolean
Summarytrue
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.

CodeSystem.valueSet
Element IdCodeSystem.valueSet
Definition

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

Control0..1
Typecanonical(ValueSet)
Summarytrue
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.

CodeSystem.hierarchyMeaning
Element IdCodeSystem.hierarchyMeaning
Definition

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

Control0..1
Terminology BindingCodeSystemHierarchyMeaning (Required)
Typecode
Summarytrue
Comments

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

CodeSystem.compositional
Element IdCodeSystem.compositional
Definition

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

Control0..1
Typeboolean
Alternate Namesgrammar
Summarytrue
Comments

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

CodeSystem.versionNeeded
Element IdCodeSystem.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.

Control0..1
Typeboolean
Summarytrue
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.

CodeSystem.content
Element IdCodeSystem.content
Definition

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

Control1..1
Terminology BindingCodeSystemContentMode (Required)
Typecode
Summarytrue
CodeSystem.supplements
Element IdCodeSystem.supplements
Definition

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

Control0..1
Typecanonical(CodeSystem)
Summarytrue
Comments

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

CodeSystem.count
Element IdCodeSystem.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.

Control0..1
TypeunsignedInt
Summarytrue
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.

CodeSystem.filter
Element IdCodeSystem.filter
Definition

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

Control0..*
Summarytrue
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.

CodeSystem.filter.code
Element IdCodeSystem.filter.code
Definition

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

Control1..1
Typecode
Summarytrue
CodeSystem.filter.description
Element IdCodeSystem.filter.description
Definition

A description of how or why the filter is used.

Control0..1
Typestring
Summarytrue
CodeSystem.filter.operator
Element IdCodeSystem.filter.operator
Definition

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

Control1..*
Terminology BindingFilterOperator (Required)
Typecode
Summarytrue
CodeSystem.filter.value
Element IdCodeSystem.filter.value
Definition

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

Control1..1
Typestring
Summarytrue
CodeSystem.property
Element IdCodeSystem.property
Definition

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

Control0..*
Summarytrue
CodeSystem.property.code
Element IdCodeSystem.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.

Control1..1
Typecode
Summarytrue
CodeSystem.property.uri
Element IdCodeSystem.property.uri
Definition

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

Control0..1
Typeuri
Summarytrue
CodeSystem.property.description
Element IdCodeSystem.property.description
Definition

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

Control0..1
Typestring
Summarytrue
CodeSystem.property.type
Element IdCodeSystem.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).

Control1..1
Terminology BindingPropertyType (Required)
Typecode
Summarytrue
CodeSystem.concept
Element IdCodeSystem.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 meaning of the hierarchical relationships are.

Control0..*
Comments

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

CodeSystem.concept.code
Element IdCodeSystem.concept.code
Definition

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

Control1..1
Typecode
CodeSystem.concept.display
Element IdCodeSystem.concept.display
Definition

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

Control0..1
Typestring
CodeSystem.concept.definition
Element IdCodeSystem.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.

Control0..1
Typestring
CodeSystem.concept.designation
Element IdCodeSystem.concept.designation
Definition

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

Control0..*
Requirements

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

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.

CodeSystem.concept.designation.language
Element IdCodeSystem.concept.designation.language
Definition

The language this designation is defined for.

Control0..1
Terminology BindingLanguage (Preferred but limited to Language)
Typecode
Comments

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

CodeSystem.concept.designation.use
Element IdCodeSystem.concept.designation.use
Definition

A code that details how this designation would be used.

Control0..1
Terminology BindingDesignation Use (Extensible)
TypeCoding
Comments

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

CodeSystem.concept.designation.value
Element IdCodeSystem.concept.designation.value
Definition

The text value for this designation.

Control1..1
Typestring
CodeSystem.concept.property
Element IdCodeSystem.concept.property
Definition

A property value for this concept.

Control0..*
CodeSystem.concept.property.code
Element IdCodeSystem.concept.property.code
Definition

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

Control1..1
Typecode
CodeSystem.concept.property.value[x]
Element IdCodeSystem.concept.property.value[x]
Definition

The value of this property.

Control1..1
Typecode|Coding|string|integer|boolean|dateTime|decimal
[x] NoteSee Choice of Data Types for further information about how to use [x]
CodeSystem.concept.concept
Element IdCodeSystem.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.

Control0..*
TypeSee CodeSystem.concept