Schizophrenia--falling incidence and better outcome?

It has been suggested that schizophrenia is a disappearing disease. The evidence for this assertion is reviewed, and also for a parallel theory advanced in recent years that the disorder may be undergoing a benign metamorphosis in its course and outcome. It is concluded that the evidence is presently unconvincing given the methodological problems inherent in most follow-up studies; changes have taken place in clinicians' assumptions, in treatments, and in the quality of follow-up studies, rather than in the disorder itself. Nevertheless, possible time trends in the incidence and outcome of schizophrenia call for further scientific investigation.