description: This cross-version extension represents MedicationKnowledge.contraindication from http://hl7.org/fhir/StructureDefinition/MedicationKnowledge|4.3.0 for use in FHIR R5. package_name: hl7.fhir.uv.xver derivation: constraint name: Ext_R4B_MedicationKnowledge_contraindication type: Extension elements: url: base: {max: '1', min: 1, path: Extension.url} pattern: {type: Uri, value: 'http://hl7.org/fhir/4.3/StructureDefinition/extension-MedicationKnowledge.contraindication'} index: 0 value: base: {max: '1', min: 0, path: 'Extension.value[x]'} short: Potential clinical issue with or between medication(s) choices: [valueReference] index: 2 valueReference: base: {max: '1', min: 0, path: 'Extension.value[x]'} type: Reference short: Potential clinical issue with or between medication(s) 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-MedicationKnowledge.contraindication base: http://hl7.org/fhir/StructureDefinition/Extension|5.0.0 version: 0.0.1-snapshot-2 required: [url]