We are still confronted by numerous different nosographic models and problems concerning the objective evaluation of patients progress during treatment. It is interesting to consider the consequences of this situation in psychiatry which still involves a relative diversity of practical methods used in clinical trials. The recommendations of the USA Food and Drug Administration, on the one hand, constitute a highly structured and precise reference. The World Health Organization, on the other hand, promulgates general recommendations resulting from a compromise designed to satisfy the greatest number of clinicians.

Despite the apparently diverse principles and the different practical methods they propose, both those sets of recommendations have been useful in inspiring clinicians to reflect upon these different methodological approaches. The qualities of the inclusion criteria used in the study of patients and the sensitivity of the different measuring instruments have allowed psychotropic drug users as well as producers to recognize the need for a certain rigour in clinical trials.

The FDA and WHO guidelines have certainly improved the quality of clinical trials in psychopharmacology. However, they also represent a source of resistance to innovation.

A series of consensus meetings to first reconcile US and European points of view and later to include new techniques in the recognized sets of methods would therefore be helpful.