NameFlagsCard.TypeDescription & Constraintsdoco
.. CommunicationRequest ΣDomainResourceA request for information to be sent to a receiver
... identifier Σ0..*IdentifierUnique identifier
... category Σ0..1CodeableConceptMessage category
... sender Σ0..1Reference(Device | Organization | Patient | Practitioner | RelatedPerson)Message sender
... recipient Σ0..*Reference(Device | Organization | Patient | Practitioner | RelatedPerson)Message recipient
... payload Σ0..*BackboneElementMessage payload
.... content[x] Σ1..1Message part content
..... contentStringstring
..... contentAttachmentAttachment
..... contentReferenceReference(Any)
... medium Σ0..*CodeableConceptA channel of communication
v3 Code System ParticipationMode (Example)
... requester Σ0..1Reference(Practitioner | Patient | RelatedPerson)An individual who requested a communication
... status ?! Σ0..1codeproposed | planned | requested | received | accepted | in-progress | completed | suspended | rejected | failed
CommunicationRequestStatus (Required)
... encounter Σ0..1Reference(Encounter)Encounter leading to message
... scheduled[x] Σ0..1When scheduled
.... scheduledDateTimedateTime
.... scheduledPeriodPeriod
... reason Σ0..*CodeableConceptIndication for message
... requestedOn Σ0..1dateTimeWhen ordered or proposed
... subject Σ0..1Reference(Patient)Focus of message
... priority Σ0..1CodeableConceptMessage urgency
DiagnosticOrderPriority (Example)

doco Documentation for this format