{description: Data Element for Period.start, package_name: hl7.fhir.r4b.elements, derivation: specialization, name: Period.start, type: Period.start, package_version: 4.3.0, class: logical, kind: logical, url: 'http://hl7.org/fhir/StructureDefinition/de-Period.start', base: 'http://hl7.org/fhir/StructureDefinition/Element', version: 4.3.0}