> ## Documentation Index > Fetch the complete documentation index at: https://docs.metriport.com/llms.txt > Use this file to discover all available pages before exploring further. # Composition > A set of healthcare-related information that is assembled together into a single logical package that provides a single coherent statement of meaning, establishes its own context and that has clinical attestation with regard to who is making the statement. A Composition defines the structure and narrative content necessary for a document. However, a Composition alone does not constitute a document. Rather, the Composition must be the first entry in a Bundle where Bundle.type=document, and any other resources referenced from Composition must be included as subsequent entries in the Bundle (for example Patient, Practitioner, Encounter, etc.). ## Properties | Name | Required | Type | Description | | ------------------- | -------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------ | | identifier | No | [Identifier](/medical-api/fhir/data-types/identifier) | Version-independent identifier for the Composition | | status | Yes | code | preliminary / final / amended / entered-in-error | | type | Yes | [CodeableConcept](/medical-api/fhir/data-types/codeableconcept) | Kind of composition (LOINC if possible) | | category | No | [CodeableConcept](/medical-api/fhir/data-types/codeableconcept)\[] | Categorization of Composition | | subject | No | Reference\ | Who and/or what the composition is about | | encounter | No | Reference\<[Encounter](/medical-api/fhir/resources/encounter)> | Context of the Composition | | date | Yes | dateTime | Composition editing time | | author | Yes | Reference\<[Practitioner](/medical-api/fhir/resources/practitioner) / [PractitionerRole](/medical-api/fhir/resources/practitionerrole) / [Device](/medical-api/fhir/resources/device) / [Patient](/medical-api/fhir/resources/patient) / [RelatedPerson](/medical-api/fhir/resources/relatedperson) / [Organization](/medical-api/fhir/resources/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](/medical-api/fhir/data-types/extension)\[] | Additional content defined by implementations | | - modifierExtension | No | [Extension](/medical-api/fhir/data-types/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](/medical-api/fhir/resources/patient) / [RelatedPerson](/medical-api/fhir/resources/relatedperson) / [Practitioner](/medical-api/fhir/resources/practitioner) / [PractitionerRole](/medical-api/fhir/resources/practitionerrole) / [Organization](/medical-api/fhir/resources/organization)> | Who attested the composition | | custodian | No | Reference\<[Organization](/medical-api/fhir/resources/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](/medical-api/fhir/data-types/extension)\[] | Additional content defined by implementations | | - modifierExtension | No | [Extension](/medical-api/fhir/data-types/extension)\[] | Extensions that cannot be ignored even if unrecognized | | - code | Yes | code | replaces / transforms / signs / appends | | - target\[x] | Yes | [Identifier](/medical-api/fhir/data-types/identifier), Reference\<[Composition](/medical-api/fhir/resources/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](/medical-api/fhir/data-types/extension)\[] | Additional content defined by implementations | | - modifierExtension | No | [Extension](/medical-api/fhir/data-types/extension)\[] | Extensions that cannot be ignored even if unrecognized | | - code | No | [CodeableConcept](/medical-api/fhir/data-types/codeableconcept)\[] | Code(s) that apply to the event being documented | | - period | No | [Period](/medical-api/fhir/data-types/period) | The period covered by the documentation | | - detail | No | Reference\\[] | 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](/medical-api/fhir/data-types/extension)\[] | Additional content defined by implementations | | - modifierExtension | No | [Extension](/medical-api/fhir/data-types/extension)\[] | Extensions that cannot be ignored even if unrecognized | | - title | No | string | Label for section (e.g. for ToC) | | - code | No | [CodeableConcept](/medical-api/fhir/data-types/codeableconcept) | Classification of section (recommended) | | - author | No | Reference\<[Practitioner](/medical-api/fhir/resources/practitioner) / [PractitionerRole](/medical-api/fhir/resources/practitionerrole) / [Device](/medical-api/fhir/resources/device) / [Patient](/medical-api/fhir/resources/patient) / [RelatedPerson](/medical-api/fhir/resources/relatedperson) / [Organization](/medical-api/fhir/resources/organization)>\[] | Who and/or what authored the section | | - focus | No | Reference\ | Who/what the section is about, when it is not about the subject of composition | | - text | No | [Narrative](/medical-api/fhir/data-types/narrative) | Text summary of the section, for human interpretation | | - mode | No | code | working / snapshot / changes | | - orderedBy | No | [CodeableConcept](/medical-api/fhir/data-types/codeableconcept) | Order of section entries | | - entry | No | Reference\\[] | A reference to data that supports this section | | - emptyReason | No | [CodeableConcept](/medical-api/fhir/data-types/codeableconcept) | Why the section is empty | | - section | No | \[] | Nested Section | ## Search Parameters | Name | Type | Description | Expression | | --------------- | --------- | -------------------------------------------------- | ---------------------------- | | date | date | Composition editing time | Composition.date | | identifier | token | Version-independent identifier for the Composition | Composition.identifier | | patient | reference | Who and/or what the composition is about | Composition.subject | | type | token | Kind of composition (LOINC if possible) | Composition.type | | attester | reference | Who attested the composition | Composition.attester.party | | author | reference | Who and/or what authored the composition | Composition.author | | category | token | Categorization of Composition | Composition.category | | confidentiality | token | As defined by affinity domain | Composition.confidentiality | | context | token | Code(s) that apply to the event being documented | Composition.event.code | | encounter | reference | Context of the Composition | Composition.encounter | | entry | reference | A reference to data that supports this section | Composition.section.entry | | period | date | The period covered by the documentation | Composition.event.period | | related-id | token | Target of the relationship | Composition.relatesTo.target | | related-ref | reference | Target of the relationship | Composition.relatesTo.target | | section | token | Classification of section (recommended) | Composition.section.code | | status | token | preliminary / final / amended / entered-in-error | Composition.status | | subject | reference | Who and/or what the composition is about | Composition.subject | | title | string | Human Readable name/title | Composition.title | ## Inherited Properties | Name | Required | Type | Description | | ----------------- | -------- | ------------------------------------------------------ | ------------------------------------------------------ | | id | No | string | Logical id of this artifact | | meta | No | [Meta](/medical-api/fhir/data-types/meta) | Metadata about the resource | | implicitRules | No | uri | A set of rules under which this content was created | | language | No | code | Language of the resource content | | text | No | [Narrative](/medical-api/fhir/data-types/narrative) | Text summary of the resource, for human interpretation | | contained | No | Resource\[] | Contained, inline Resources | | extension | No | [Extension](/medical-api/fhir/data-types/extension)\[] | Additional content defined by implementations | | modifierExtension | No | [Extension](/medical-api/fhir/data-types/extension)\[] | Extensions that cannot be ignored | To view the FHIR specification for this resource, see [Composition](https://www.hl7.org/fhir/StructureDefinition/Composition).