This is the CodeSystem that contains all the codes in US Core Category (http://hl7.org/fhir/us/core/CodeSystem/us-core-category) and US Core Category (http://hl7.org/fhir/us/core/CodeSystem/us-core-category). E.g. what you have to deal with if you get resources containing codes in either of them
Generated Narrative: CodeSystem efa809c9-a3af-4d45-b259-5658992532c3-8
This code system http://hl7.org/fhir/comparison/CodeSystem/efa809c9-a3af-4d45-b259-5658992532c3-8 defines codes, but no codes are represented here