Name	Flags	Card.	Type	Description & Constraints
MessageHeader	TU		DomainResource	A resource that describes a message that is exchanged between systems Elements defined in Ancestors: id, meta, implicitRules, language, text, contained, extension, modifierExtension
event[x]	Σ	1..1		The real world event that triggered this messsage Binding: MessageEvent ( Example)
eventCoding			Coding
eventUri			uri
eventCanonical			canonical( EventDefinition | SubscriptionTopic)
destination	Σ	0..*	BackboneElement	Message destination application(s)
endpoint[x]	Σ	0..1		Actual destination address or Endpoint resource
endpointUrl			url
endpointReference			Reference( Endpoint)
name	Σ	0..1	string	Name of system
receiver	Σ	0..1	Reference( Device | Organization | Patient | Practitioner | PractitionerRole | RelatedPerson)	Intended "real-world" recipient for the data
source	Σ	1..1	BackboneElement	Message source application
endpoint[x]	Σ	0..1		Actual source address or Endpoint resource
endpointUrl			url
endpointReference			Reference( Endpoint)
name	Σ	0..1	string	Name of system
software	Σ	0..1	string	Name of software running the system
version	Σ	0..1	string	Version of software running
contact	Σ	0..1	ContactPoint	Human contact for problems
sender	Σ	0..1	Reference( Device | Organization | Patient | Practitioner | PractitionerRole)	Real world sender of the message
reason	Σ	0..1	CodeableConcept	Cause of event Binding: Example Message Reason Codes ( Example)
response	Σ	0..1	BackboneElement	If this is a reply to prior message
identifier	Σ	1..1	Identifier	Bundle.identifier of original message
code	Σ	1..1	code	ok | transient-error | fatal-error Binding: Response Type ( Required)
details	Σ	0..1	Reference( OperationOutcome)	Specific list of hints/warnings/errors
focus	Σ	0..*	Reference( Any)	The actual content of the message
definition	Σ	0..1	canonical( MessageDefinition)	Link to the definition for this message
Documentation for this format