It is in that spirit that we provide the following overview of controlled clinical trials in schizophrenia. We will first discuss the changing clinical and scientific context in which RCTs are taking place, followed by a discussion of specific trial components and their importance. Historical developments The somewhat serendipitous observation that chlorpromazine had a pronounced “calming” activity that extended to benefits for psychotic

signs and symptoms was one of the great advances in 20th-century medicine. This effect was observed without the benefit of an RCT. Chlorpromazine was subsequently approved by the Food and Drug Administration Inhibitors,research,lifescience,medical in 1954, and by 1964, approximately 50 million people around the world had been treated with this medication. In 1949, the World Health Organization

published the sixth revision of the International Inhibitors,research,lifescience,medical Statistical Classification of Diseases (ICD), which for the first time included a section on mental disorders.1 The first official Diagnostic and Statistical Manual Inhibitors,research,lifescience,medical of Mental Disorders (DSM) was published in 1952 by the American Akt inhibitor in vivo Psychiatric Association.2 Diagnostic criteria were not really specified for discrete disorders until the third edition of DSM (III),3 which attempted to improve the validity and reliability of psychiatric diagnosis. This, in turn, had enormous implications for clinical practice, clinical research and drug development. In 1969, Klein and Davis published a seminal work entitled Diagnosis and Drug Treatment of Psychiatric Disorders. 4 In the introduction, they wrote, “We may be fortunate to be entering a period in which rational comparative Inhibitors,research,lifescience,medical study will become standard for therapeutic Inhibitors,research,lifescience,medical decision. Although clinical hunches and results of clinical experience are important factors in the determination of proper treatment, the findings of research studies, particularly those which are done with controlled double-blind technique, provide the behavioral scientific data for informed

decision.” By 1969, Klein and Davis identified 126 controlled studies comparing antipsychotic Parvulin drugs and placebo in which the medications were found to be more effective and 26 comparisons in which they were not.“ They also examined the role of dose adequacy and found that most of those studies that found chlorpromazine to be ineffective used very small doses, and all 23 studies that employed doses over 500 mg/day were positive. Similarly, in all studies, which were judged to be methodologically rigorous, the phenothiazine derivatives (and reserpine) were shown to be more effective than the control conditions. These data led to an enormous shift in clinical practice, with antipsychotic drugs becoming the critical component in the treatment of schizophrenia.