This is the CodeSystem that contains all the codes in ICAO lab test result codes used in this IG (http://smart.who.int/ddcc/CodeSystem/WHODDCCicaolabtestresult) and ICAO lab test result codes used in this IG (http://smart.who.int/ddcc/CodeSystem/WHODDCCicaolabtestresult). E.g. what you have to deal with if you get resources containing codes in either of them