description: Where it is necessary to reference an external clinical document, the External Document Reference template can be used to reference this external document. However, if the containing document is appending to or replacing another document in the same set, that relationship is set in the header, using ClinicalDocument/relatedDocument.
package_name: hl7.cda.us.ccda
derivation: constraint
name: ExternalDocumentReference
type: http://hl7.org/cda/stds/core/StructureDefinition/ExternalDocument
elements:
  templateId:
    index: 0
    slicing:
      rules: open
      discriminator:
      - {path: root, type: value}
      - {path: extension, type: value}
      min: 1
      slices:
        external-doc-ref:
          match: {root: 2.16.840.1.113883.10.20.22.4.115, extension: '2014-06-09'}
          schema:
            _required: true
            index: 1
            elements:
              root:
                pattern: {type: String, value: 2.16.840.1.113883.10.20.22.4.115}
                index: 2
              extension:
                pattern: {type: String, value: '2014-06-09'}
                index: 3
            required: [root, extension]
            extensions: {}
  classCode:
    pattern: {type: Code, value: DOCCLIN}
    index: 4
  moodCode: {index: 5}
  id: {index: 6}
  code: {index: 7}
  setId: {index: 8}
  versionNumber: {index: 9}
package_version: 3.0.0-ballot
class: logical
kind: logical
url: http://hl7.org/cda/us/ccda/StructureDefinition/ExternalDocumentReference
base: http://hl7.org/cda/stds/core/StructureDefinition/ExternalDocument
version: 3.0.0-ballot
required: [classCode, id, moodCode, templateId, code]