This is the ValueSet that contains all the codes in eHDSI Presence Absence (http://terminology.ehdsi.eu/ValueSet/eHDSIPresenceAbsence) and eHDSI Presence Absence (http://terminology.ehdsi.eu/ValueSet/eHDSIPresenceAbsence). E.g. what you have to deal with if you get resources containing codes in either of them