description: This cross-version extension represents Communication.reasonReference from http://hl7.org/fhir/StructureDefinition/Communication|4.3.0 for use in FHIR R5. package_name: hl7.fhir.uv.xver derivation: constraint name: Ext_R4B_Communication_reasonReference type: Extension elements: url: base: {max: '1', min: 1, path: Extension.url} pattern: {type: Uri, value: 'http://hl7.org/fhir/4.3/StructureDefinition/extension-Communication.reasonReference'} index: 0 value: base: {max: '1', min: 0, path: 'Extension.value[x]'} short: Why was communication done? choices: [valueReference] index: 2 valueReference: base: {max: '1', min: 0, path: 'Extension.value[x]'} type: Reference short: Why was communication done? choiceOf: value index: 3 package_version: r4b.r5-0.0.1-snapshot-2 class: extension kind: complex-type url: http://hl7.org/fhir/4.3/StructureDefinition/extension-Communication.reasonReference base: http://hl7.org/fhir/StructureDefinition/Extension|5.0.0 version: 0.0.1-snapshot-2 required: [url]