The NEMS Event Message Bundle Structure
To enable a standardised structure to carry information within the scope of the National Events Management Service, the NEMS Message Bundle and the NEMS Message Header combine to make up the initial event message bundle structure:
This is consistent with the FHIR specification for the Bundle resource, which states that ‘A message bundle (type = “message”) consists of a series of entries, the first of which is a MessageHeader.’
MessageHeader focus
The root class of the MessageHeader is fulfilled using the ‘focus’ element in the resource. This will reference the appropriate resource depending on the following conditions:
- for clinical events, the ‘focus’ will reference an Encounter resource
- for information alerts or updates, the ‘focus’ will reference a Communication resource
- for any other events yet to be scoped, it is expected that the ‘focus’ may be any FHIR resource where the ‘subject’ element is fulfilled by a reference to a Patient resource.
The NEMS Event Message Bundle Structure with Event Header Items
The following components are then added to the initial NEMS Event Message Bundle structure in order to fulfill the event header requirement.
Organization resources in NEMS Event Message Bundle Structure
Where possible, the NEMS bundle will contain an absolute URL reference to an Organization resource, which can be retrieved as described in the FHIR ODS Lookup API Implementation guide.
The NEMS Event Message Bundle Structure with NEMS Data Items
Finally, using the National Failsafe Alert for National Population Failsafe Management (NPFM) as an example, the following components are added to the NEMS Event Message Bundle structure in order to fulfill the data item requirements specific to the event.
