Aussagekraft offener Studien im Vergleich zu kontrollierten Studien in der Prüfung von Neuroleptika

Objective Due to methodological reservations, results concerning the efficacy of neuroleptics in open trials are often regarded with doubt. Until now, there are nearly no studies comparing findings of controlled double-blind with those of open trials. Aim of this study was to investigate if results of an open or double-blind approach differ and hereby to gain information about the validity of open trials.Methods After a literature research, five neuroleptics were identified for which at least 3 open and 3 double-blind trials exist which met the inclusion criteria and from which either the reduction of the BPRS (Brief Psychiatric Rating Scale)-score or the response rate could be determined.Results There were no differences in the reduction of the BPRS-score or response rate for all 5 neuroleptics between open and double-blind trials. Furthermore, the efficacy of all 5 neuroleptics was comparable.Conclusions Double-blind controlled studies are essential in the investigation of new compounds. But results of methodologically well performed open studies are valid and deserve more attention. Preceding open trials may help in the design of double-blind studies.