The relationship between diagnostic assignment and specific symptomatology on admission and the duration of the first hospital stay was investigated in 200 patients with a functional psychosis. There were considerable differences in the mean duration of stay in hospital for patients fulfilling different diagnostic criteria for schizophrenia: the broader the concept of schizophrenia, the shorter the duration of stay. In looking at symptomatology, it could be demonstrated that patients with formal thought disorder had the highest mean duration of first inpatient episode.