This is the ValueSet that contains all the codes in Problem Type (LOINC) (http://hl7.org/fhir/uv/ips/ValueSet/problem-type-loinc) and Problem Type (LOINC) (http://hl7.org/fhir/uv/ips/ValueSet/problem-type-loinc). E.g. what you have to deal with if you get resources containing codes in either of them