description: Provides a reason why the expected value or elements in the element that is extended are missing. package_name: hl7.fhir.core derivation: constraint name: Data Absent Reason type: Extension elements: extension: index: 0 slicing: slices: extension: match: {} schema: {index: 0} max: 0 url: type: uri pattern: {type: Uri, value: 'http://hl7.org/fhir/StructureDefinition/data-absent-reason'} index: 1 value: choices: [valueCode] index: 3 valueCode: {type: code, choiceOf: value, index: 4} package_version: 1.8.0 extensions: extension: {url: null, max: 0, index: 0} class: extension kind: complex-type url: http://hl7.org/fhir/StructureDefinition/data-absent-reason base: http://hl7.org/fhir/StructureDefinition/Extension version: null required: [valueCode, value]