Union of http://terminology.hl7.org/CodeSystem/med-admin-perform-function and http://terminology.hl7.org/CodeSystem/med-admin-perform-function

This is the CodeSystem that contains all the codes in MedicationAdministration Performer Function Codes (http://terminology.hl7.org/CodeSystem/med-admin-perform-function) and MedicationAdministration Performer Function Codes (http://terminology.hl7.org/CodeSystem/med-admin-perform-function). E.g. what you have to deal with if you get resources containing codes in either of them

CodeSystem

Generated Narrative: CodeSystem 818959f7-0f8d-4f6f-b46c-7c5a5833d862-635

This code system http://hl7.org/fhir/comparison/CodeSystem/818959f7-0f8d-4f6f-b46c-7c5a5833d862-635 defines codes, but no codes are represented here

CodeDisplayDefinition
performer PerformerA person, non-person living subject, organization or device that who actually and principally carries out the action
verifier VerifierA person who verifies the correctness and appropriateness of the service (plan, order, event, etc.) and hence takes on accountability.
witness WitnessA person witnessing the action happening without doing anything. A witness is not necessarily aware, much less approves of anything stated in the service event. Example for a witness is students watching an operation or an advanced directive witness.