description: Specifies that a date is relative to some event. The event happens [Duration] after [Event]. package_name: hl7.fhir.r4.examples derivation: constraint name: Relative Date Criteria type: Extension elements: extension: short: Event that the date is relative to type: Extension index: 0 slicing: slices: event: match: {} schema: short: Event that the date is relative to type: Extension _required: true index: 0 extensions: {} elements: extension: {index: 1} url: type: uri pattern: {type: Uri, value: event} index: 2 value: choices: [valueReference, valueCodeableConcept] index: 4 valueReference: type: Reference choiceOf: value refers: ['http://hl7.org/fhir/StructureDefinition/Resource'] index: 5 valueCodeableConcept: {type: CodeableConcept, choiceOf: value, index: 6} required: [valueReference, value, valueCodeableConcept] relationship: match: {} schema: type: Extension short: before-start | before | before-end | concurrent-with-start | concurrent | concurrent-with-end | after-start | after | after-end _required: true index: 7 extensions: {} elements: extension: {index: 8} url: type: uri pattern: {type: Uri, value: relationship} index: 9 value: choices: [valueCode] index: 11 valueCode: {type: code, choiceOf: value, index: 12} required: [valueCode, value] offset: match: {} schema: type: Extension short: Duration after the event _required: true index: 13 extensions: {} elements: extension: {index: 14} url: type: uri pattern: {type: Uri, value: offset} index: 15 value: choices: [valueDuration] index: 17 valueDuration: {type: Duration, choiceOf: value, index: 18} required: [value, valueDuration] url: pattern: {type: Uri, value: 'http://hl7.org/fhir/StructureDefinition/relative-date'} index: 19 value: choices: [] index: 21 package_version: 4.0.1 extensions: event: url: null short: Event that the date is relative to type: Extension _required: true index: 0 extensions: {} elements: extension: {index: 1} url: type: uri pattern: {type: Uri, value: event} index: 2 value: choices: [valueReference, valueCodeableConcept] index: 4 valueReference: type: Reference choiceOf: value refers: ['http://hl7.org/fhir/StructureDefinition/Resource'] index: 5 valueCodeableConcept: {type: CodeableConcept, choiceOf: value, index: 6} required: [valueReference, value, valueCodeableConcept] relationship: url: null type: Extension short: before-start | before | before-end | concurrent-with-start | concurrent | concurrent-with-end | after-start | after | after-end _required: true index: 7 extensions: {} elements: extension: {index: 8} url: type: uri pattern: {type: Uri, value: relationship} index: 9 value: choices: [valueCode] index: 11 valueCode: {type: code, choiceOf: value, index: 12} required: [valueCode, value] offset: url: null type: Extension short: Duration after the event _required: true index: 13 extensions: {} elements: extension: {index: 14} url: type: uri pattern: {type: Uri, value: offset} index: 15 value: choices: [valueDuration] index: 17 valueDuration: {type: Duration, choiceOf: value, index: 18} required: [value, valueDuration] class: extension kind: complex-type url: http://hl7.org/fhir/StructureDefinition/relative-date base: http://hl7.org/fhir/StructureDefinition/Extension version: 4.0.1 required: [extension]