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 d3f58e09-e7d1-4613-baa2-1e58f9a06981-8
This code system http://hl7.org/fhir/comparison/CodeSystem/d3f58e09-e7d1-4613-baa2-1e58f9a06981-8
defines codes, but no codes are represented here