Clinical trials in psychiatry: background and statistical perspective

There have been many hundreds of studies which have examined the efficacy of different forms of treatment of psychiatric disorders over the past 40 years. This paper presents some background to these studies for statisticians, illustrating and discussing some of the difficult problems which arise in this specialty of medicine. It also demonstrates a major requirement for statisticians to influence both the design and presentation of clinical trials and provides some suggestions about how this may be done.