| identifier | No | Identifier | Version-independent identifier for the Composition |
| status | Yes | code | preliminary / final / amended / entered-in-error |
| type | Yes | CodeableConcept | Kind of composition (LOINC if possible) |
| category | No | CodeableConcept[] | Categorization of Composition |
| subject | No | Reference<Resource> | Who and/or what the composition is about |
| encounter | No | Reference<Encounter> | Context of the Composition |
| date | Yes | dateTime | Composition editing time |
| author | Yes | Reference<Practitioner / PractitionerRole / Device / Patient / RelatedPerson / Organization>[] | Who and/or what authored the composition |
| title | Yes | string | Human Readable name/title |
| confidentiality | No | code | As defined by affinity domain |
| attester | No | CompositionAttester | Attests to accuracy of composition |
| - id | No | string | Unique id for inter-element referencing |
| - extension | No | Extension[] | Additional content defined by implementations |
| - modifierExtension | No | Extension[] | Extensions that cannot be ignored even if unrecognized |
| - mode | Yes | code | personal / professional / legal / official |
| - time | No | dateTime | When the composition was attested |
| - party | No | Reference<Patient / RelatedPerson / Practitioner / PractitionerRole / Organization> | Who attested the composition |
| custodian | No | Reference<Organization> | Organization which maintains the composition |
| relatesTo | No | CompositionRelatesTo | Relationships to other compositions/documents |
| - id | No | string | Unique id for inter-element referencing |
| - extension | No | Extension[] | Additional content defined by implementations |
| - modifierExtension | No | Extension[] | Extensions that cannot be ignored even if unrecognized |
| - code | Yes | code | replaces / transforms / signs / appends |
| - target[x] | Yes | Identifier, Reference<Composition> | Target of the relationship |
| event | No | CompositionEvent | The clinical service(s) being documented |
| - id | No | string | Unique id for inter-element referencing |
| - extension | No | Extension[] | Additional content defined by implementations |
| - modifierExtension | No | Extension[] | Extensions that cannot be ignored even if unrecognized |
| - code | No | CodeableConcept[] | Code(s) that apply to the event being documented |
| - period | No | Period | The period covered by the documentation |
| - detail | No | Reference<Resource>[] | The event(s) being documented |
| section | No | CompositionSection | Composition is broken into sections |
| - id | No | string | Unique id for inter-element referencing |
| - extension | No | Extension[] | Additional content defined by implementations |
| - modifierExtension | No | Extension[] | Extensions that cannot be ignored even if unrecognized |
| - title | No | string | Label for section (e.g. for ToC) |
| - code | No | CodeableConcept | Classification of section (recommended) |
| - author | No | Reference<Practitioner / PractitionerRole / Device / Patient / RelatedPerson / Organization>[] | Who and/or what authored the section |
| - focus | No | Reference<Resource> | Who/what the section is about, when it is not about the subject of composition |
| - text | No | Narrative | Text summary of the section, for human interpretation |
| - mode | No | code | working / snapshot / changes |
| - orderedBy | No | CodeableConcept | Order of section entries |
| - entry | No | Reference<Resource>[] | A reference to data that supports this section |
| - emptyReason | No | CodeableConcept | Why the section is empty |
| - section | No | [] | Nested Section |
