Decreasing rates of incident schizophrenia cases in psychiatric service: A review of the literature.

A review of the literature shows that the admission rates of new cases of schizophrenia vary with a factor of two to five in North American studies as well as in European studies. Furthermore, the tendency has been decreasing for the last 40-50 years in Europe. Eighteen studies specifically analyzing the development over the last 20 years are reviewed. The studies preponderantly show significant decreases most probably due to the reduction of the number of available psychiatric beds alongside the decentralization of psychiatry, and to decreasing virulence of schizophrenia. Alternatively, a diagnostic delay of schizophrenia can hardly explain the decrease.