description: Specifies that the section has a different subject that the Composition, or it's container section. package_name: hl7.fhir.r4b.core derivation: constraint name: section-subject type: Extension elements: extension: {index: 0} url: pattern: {type: Uri, value: 'http://hl7.org/fhir/StructureDefinition/composition-section-subject'} index: 1 value: choices: [valueString] index: 3 valueString: {type: string, choiceOf: value, index: 4} package_version: 4.3.0 extensions: {} class: extension kind: complex-type url: http://hl7.org/fhir/StructureDefinition/composition-section-subject base: http://hl7.org/fhir/StructureDefinition/Extension version: 4.3.0 required: [valueString, value]