FHIR Extensions Pack
5.4.0 - May 2026 International flag

FHIR Extensions Pack, published by HL7 International / FHIR Infrastructure. This guide is not an authorized publication; it is the continuous build for version 5.4.0 built by the FHIR (HL7® FHIR® Standard) CI Build. This version is based on the current content of https://github.com/HL7/fhir-extensions/ and changes regularly. See the Directory of published versions

Extension: CodeSystem Label

Official URL: http://hl7.org/fhir/StructureDefinition/codesystem-label Version: 5.4.0
Standards status: Trial-use Maturity Level: 3 Responsible: HL7 International / Terminology Infrastructure Computable Name: CSLabel
Other Identifiers: OID:2.16.840.1.113883.4.642.5.1152

This extension is for use when rendering lists of code choices for human selection (typically in Questionnaires). It allows specifying a prefix to put in front of the display name of the code display value. For example "a)", or "iii." or "1]". While in most situations the similar valueset-label extension would be used instead, if the value set is intensionally defined as "all codes from code system [some code system]", then the labels need to appear in the CodeSystem rather than the ValueSet. Note that this will generally not work well for intensional value sets with filters as the labels would usually end up not being sequential.

Prefixes are particularly relevant if there are textual instructions that accompany the question. E.g. 'Do not select more than one of options a, b, or c' on a multi-select question.

Context of Use

This extension may be used on the following element(s)

Usage info

Usages:

  • This Extension is not used by any profiles in this Specification

You can also check for usages in the FHIR IG Statistics

Changes since version 5.3.0:

  • One or more text definitions, invariants or bindings have changed (description)

    • Formal Views of Extension Content

    Description of Profiles, Differentials, Snapshots, and how the XML and JSON presentations work.

    This structure is derived from Extension

    Summary

    Simple Extension with the type string: This extension is for use when rendering lists of code choices for human selection (typically in Questionnaires). It allows specifying a prefix to put in front of the display name of the code display value. For example "a)", or "iii." or "1]". While in most situations the similar valueset-label extension would be used instead, if the value set is intensionally defined as "all codes from code system [some code system]", then the labels need to appear in the CodeSystem rather than the ValueSet. Note that this will generally not work well for intensional value sets with filters as the labels would usually end up not being sequential.

    Prefixes are particularly relevant if there are textual instructions that accompany the question. E.g. 'Do not select more than one of options a, b, or c' on a multi-select question.

    Maturity: 3

    This structure is derived from Extension

    NameFlagsCard.TypeDescription & Constraints    Filter: doco
    Extension 0..1 Extension E.g. "(a)", "1.", etc.
    Extension.extension 0..0 Extension
    Extension.url 1..1 uri "http://hl7.org/fhir/StructureDefinition/codesystem-label"
    Extension.value[x] 1..1 string Value of extension

    doco Documentation for this format
    NameFlagsCard.TypeDescription & Constraints    Filter: doco
    Extension 0..1 Extension E.g. "(a)", "1.", etc.
    Extension.id 0..1 id Unique id for inter-element referencing
    Extension.extension 0..0 Extension
    Slice: Unordered, Open by value:url

    Slicing Note: The rules on this element (including its children) apply to all the slices, but are not repeated in them
    Extension.url 1..1 uri "http://hl7.org/fhir/StructureDefinition/codesystem-label"
    Extension.value[x] 1..1 string Value of extension

    doco Documentation for this format

    This structure is derived from Extension

    Summary

    Simple Extension with the type string: This extension is for use when rendering lists of code choices for human selection (typically in Questionnaires). It allows specifying a prefix to put in front of the display name of the code display value. For example "a)", or "iii." or "1]". While in most situations the similar valueset-label extension would be used instead, if the value set is intensionally defined as "all codes from code system [some code system]", then the labels need to appear in the CodeSystem rather than the ValueSet. Note that this will generally not work well for intensional value sets with filters as the labels would usually end up not being sequential.

    Prefixes are particularly relevant if there are textual instructions that accompany the question. E.g. 'Do not select more than one of options a, b, or c' on a multi-select question.

    Maturity: 3

    Differential View

    This structure is derived from Extension

    NameFlagsCard.TypeDescription & Constraints    Filter: doco
    Extension 0..1 Extension E.g. "(a)", "1.", etc.
    Extension.extension 0..0 Extension
    Extension.url 1..1 uri "http://hl7.org/fhir/StructureDefinition/codesystem-label"
    Extension.value[x] 1..1 string Value of extension

    doco Documentation for this format

    Snapshot View

    NameFlagsCard.TypeDescription & Constraints    Filter: doco
    Extension 0..1 Extension E.g. "(a)", "1.", etc.
    Extension.id 0..1 id Unique id for inter-element referencing
    Extension.extension 0..0 Extension
    Slice: Unordered, Open by value:url

    Slicing Note: The rules on this element (including its children) apply to all the slices, but are not repeated in them
    Extension.url 1..1 uri "http://hl7.org/fhir/StructureDefinition/codesystem-label"
    Extension.value[x] 1..1 string Value of extension

    doco Documentation for this format

     

    Other representations of profile: CSV, Excel, Schematron

    Constraints

    Id Grade Path(s) Description Expression
    ele-1 error **ALL** elements All FHIR elements must have a @value or children hasValue() or (children().count() > id.count())
    ext-1 error **ALL** extensions Must have either extensions or value[x], not both extension.exists() != value.exists()

    R4B

    The extension is unchanged in R4B

    R4

    The extension is unchanged in R4

    R3

    The extension is unchanged in R3

    Search Parameters for this Extension

    (none found)