This is the ValueSet that contains all the codes in RoleClassICSRInvestigationSubject (http://terminology.hl7.org/ValueSet/v3-RoleClassICSRInvestigationSubject) and RoleClassICSRInvestigationSubject (http://terminology.hl7.org/ValueSet/v3-RoleClassICSRInvestigationSubject). E.g. what you have to deal with if you get resources containing codes in either of them