Long-term outcome of schizoaffective and schizophrenic disorders: a comparative study. I. Definitions, methods, psychopathological and social outcome.

The long-term outcome of 72 schizoaffective and 97 schizophrenic patients with a mean duration of illness of 25.6 years and 19.6 years respectively was investigated. The outcome was assessed using the WHO Disability Assessment Schedule (WHO/DAS), the Psychological Impairment Rating Schedule (PIRS) (also developed by the WHO), the Global Assessment Scale (GAS), and the Bonn Psychopathological Criteria of Outcome. The outcome of schizoaffective disorders was found to differ from that of schizophrenia in several ways: (a) schizoaffectives achieve a full remission significantly more frequently than schizophrenics (50% vs 10%); (b) the development of so-called characteristic schizophrenic residua is the exception in schizoaffective disorders, but is frequent in schizophrenia; (c) disability, psychological impairment and disturbances of the level of functioning are not only significantly less frequent in schizoaffective disorders but are also less intense than in the schizophrenic group. The factors influencing the outcome of the two disorders are different (see part II), as are the social consequences (part III).