description: A comment that explains how this code is used in this context (where the value set is expected to be used). package_name: hl7.fhir.uv.extensions.r4b derivation: constraint name: VSConceptComments type: Extension elements: extension: {index: 0} url: pattern: {type: uri, value: 'http://hl7.org/fhir/StructureDefinition/valueset-concept-comments'} type: uri index: 1 value: choices: [valueString] index: 3 valueString: {type: string, choiceOf: value, index: 4} package_version: 5.3.0-ballot-tc extensions: {} class: extension kind: complex-type url: http://hl7.org/fhir/StructureDefinition/valueset-concept-comments base: http://hl7.org/fhir/StructureDefinition/Extension version: 5.3.0-ballot-tc required: [value, valueString]