The scientific development of a medical speciality is reflected in the number of specialists who have written a thesis (dissertation). About 12.5% of the psychiatrists have done this. This is a relatively low number in comparison with internal medicine and surgery. Through a period of fourty years there was a `dip in the seventies. In the last decade there was an increase. The number of dissertations on subjects within the areas of psychogeriatric diagnosis/treatment of addiction was relatively small.