Patient.identifier(NHSNumber).system is http://fhir.nhs.net/Id/nhs-number but API implementation documentation uses urn:fhir.nhs.uk:id/NHSNumber. I assume urls supersede urns?
Patient.identifier (OtherPatientIdentifier) binding implies use in Scotland (e.g. CHI), but Patient.identifier (NhsNumber) is mandatory. Is there an ambition for the profiles to be used in outside England?
Could mandatory be changed to a recommendation/should? Mandatory tends to cause more problems than they solve - ideal world is rare.
As it stands, it implies UK wide use and so needs cardinality greater than one to include patients who also have both English/Welsh or Scottish NHS Numbers (and some citizens have requested a new number when they moved to Scotland).
The reply might be late but may still be relavant.
The patient NHS Number identifier system is now consistent between the FHIR Resource Profiles and the GP Connect API specification with the value “https://fhir.nhs.uk/Id/nhs-number”.
The current GP Connect profiles contain a slice for the NHS number identifier, but the NHS Number business identifier is optional within the profile so other business identifiers could be used instead of the NHS Number if the NHS Number is not available.
The specification has also been changed since the origional issue was raised, the specification now uses the NHS number as an example for all interactions centred around the patient but wording has been updated to make clear that the NHS Number shall be supported by providers, but providers may support additional business identifiers if they wish to use the API and profiles outside of England, this is currently out of scope though.