> ## 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. # CommunicationRequest > A request to convey information; e.g. the CDS system proposes that an alert be sent to a responsible provider, the CDS system proposes that the public health agency be notified about a reportable condition. ## Properties | Name | Required | Type | Description | | ------------------- | -------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------------------- | | identifier | No | [Identifier](/medical-api/fhir/data-types/identifier)\[] | Unique identifier | | basedOn | No | Reference\\[] | Fulfills plan or proposal | | replaces | No | Reference\<[CommunicationRequest](/medical-api/fhir/resources/communicationrequest)>\[] | Request(s) replaced by this request | | groupIdentifier | No | [Identifier](/medical-api/fhir/data-types/identifier) | Composite request this is part of | | status | Yes | code | draft / active / on-hold / revoked / completed / entered-in-error / unknown | | statusReason | No | [CodeableConcept](/medical-api/fhir/data-types/codeableconcept) | Reason for current status | | category | No | [CodeableConcept](/medical-api/fhir/data-types/codeableconcept)\[] | Message category | | priority | No | code | routine / urgent / asap / stat | | doNotPerform | No | boolean | True if request is prohibiting action | | medium | No | [CodeableConcept](/medical-api/fhir/data-types/codeableconcept)\[] | A channel of communication | | subject | No | Reference\<[Patient](/medical-api/fhir/resources/patient) / [Group](/medical-api/fhir/resources/group)> | Focus of message | | about | No | Reference\\[] | Resources that pertain to this communication request | | encounter | No | Reference\<[Encounter](/medical-api/fhir/resources/encounter)> | Encounter created as part of | | payload | No | CommunicationRequestPayload | Message payload | | - 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 | | - content\[x] | Yes | string, [Attachment](/medical-api/fhir/data-types/attachment), Reference\ | Message part content | | occurrence\[x] | No | dateTime, [Period](/medical-api/fhir/data-types/period) | When scheduled | | authoredOn | No | dateTime | When request transitioned to being actionable | | requester | No | Reference\<[Practitioner](/medical-api/fhir/resources/practitioner) / [PractitionerRole](/medical-api/fhir/resources/practitionerrole) / [Organization](/medical-api/fhir/resources/organization) / [Patient](/medical-api/fhir/resources/patient) / [RelatedPerson](/medical-api/fhir/resources/relatedperson) / [Device](/medical-api/fhir/resources/device)> | Who/what is requesting service | | recipient | No | Reference\<[Device](/medical-api/fhir/resources/device) / [Organization](/medical-api/fhir/resources/organization) / [Patient](/medical-api/fhir/resources/patient) / [Practitioner](/medical-api/fhir/resources/practitioner) / [PractitionerRole](/medical-api/fhir/resources/practitionerrole) / [RelatedPerson](/medical-api/fhir/resources/relatedperson) / [Group](/medical-api/fhir/resources/group) / [CareTeam](/medical-api/fhir/resources/careteam) / [HealthcareService](/medical-api/fhir/resources/healthcareservice)>\[] | Message recipient | | sender | No | Reference\<[Device](/medical-api/fhir/resources/device) / [Organization](/medical-api/fhir/resources/organization) / [Patient](/medical-api/fhir/resources/patient) / [Practitioner](/medical-api/fhir/resources/practitioner) / [PractitionerRole](/medical-api/fhir/resources/practitionerrole) / [RelatedPerson](/medical-api/fhir/resources/relatedperson) / [HealthcareService](/medical-api/fhir/resources/healthcareservice)> | Message sender | | reasonCode | No | [CodeableConcept](/medical-api/fhir/data-types/codeableconcept)\[] | Why is communication needed? | | reasonReference | No | Reference\<[Condition](/medical-api/fhir/resources/condition) / [Observation](/medical-api/fhir/resources/observation) / [DiagnosticReport](/medical-api/fhir/resources/diagnosticreport) / [DocumentReference](/medical-api/fhir/resources/documentreference)>\[] | Why is communication needed? | | note | No | [Annotation](/medical-api/fhir/data-types/annotation)\[] | Comments made about communication request | ## Search Parameters | Name | Type | Description | Expression | | ---------------- | --------- | --------------------------------------------------------------------------- | ------------------------------------ | | authored | date | When request transitioned to being actionable | CommunicationRequest.authoredOn | | based-on | reference | Fulfills plan or proposal | CommunicationRequest.basedOn | | category | token | Message category | CommunicationRequest.category | | encounter | reference | Encounter created as part of | CommunicationRequest.encounter | | group-identifier | token | Composite request this is part of | CommunicationRequest.groupIdentifier | | identifier | token | Unique identifier | CommunicationRequest.identifier | | medium | token | A channel of communication | CommunicationRequest.medium | | occurrence | date | When scheduled | CommunicationRequest.occurrence | | patient | reference | Focus of message | CommunicationRequest.subject | | priority | token | routine / urgent / asap / stat | CommunicationRequest.priority | | recipient | reference | Message recipient | CommunicationRequest.recipient | | replaces | reference | Request(s) replaced by this request | CommunicationRequest.replaces | | requester | reference | Who/what is requesting service | CommunicationRequest.requester | | sender | reference | Message sender | CommunicationRequest.sender | | status | token | draft / active / on-hold / revoked / completed / entered-in-error / unknown | CommunicationRequest.status | | subject | reference | Focus of message | CommunicationRequest.subject | ## 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 [CommunicationRequest](https://www.hl7.org/fhir/StructureDefinition/CommunicationRequest).