I have contributed two SAS macros that I made many years ago which I have found useful when working with the Swedish population based registries.
%DateNum; SAS macro for transforming alphanumeric dates (YYYYMMDD) into numeric SAS dates. The macro "corrects" dates that are incomplete or "wrong" into dates that can be stored as a numeric SAS date.
%PINq; SAS macro for checking if a personal identity number or a co-ordination number is formally correct. This only implies that the number has a valid date and that the check digit is correct, given the other digits. It does not necessarily mean that the number is in use or has been used by a person or that it has been issued by the Tax Agency.
Information from the Tax Agency about population registration in Sweden in general and the personal identity number and the co-ordination number. http://www.skatteverket.se/privat/sjalvservice/blanketterbroschyrer/broschyrer/info/717b.4.39f16f103821c58f680008017.html http://www.skatteverket.se/privat/sjalvservice/blanketterbroschyrer/broschyrer/info/704.4.39f16f103821c58f680007993.html http://www.skatteverket.se/privat/sjalvservice/blanketterbroschyrer/broschyrer/info/707.4.39f16f103821c58f680007997.html