The Danish Conscription Registry: a resource for epidemiological research.

According to the Danish constitution all Danish male citizens must appear before a Conscript Board for assessment prior to military or civil service. Conscript Board examinations have followed the same standardized procedures over many decades, and the Danish Conscript Registry represents a valuable resource for epidemiological research in Denmark. During the last two decades investigations based on information in the registry have produced significant contributions to many areas of medical science. Within the last decade new procedures and electronic data processing and storage have resulted in restricted possibilities concerning current and future utilization of the Danish Conscript Registry for epidemiological purposes. To improve this it is recommended to maintain all codes describing present illnesses and conditions together with the civic registration numbers in the computerized archive of all subjects assessed by the Conscript Board.