Stability of psychiatric diagnoses among acutely ill patients.

A survey of patients admitted four or more times to the same acute care psychiatric hospital over a period of 3 years revealed that only 56 of 162 (34%) of such patients were discharged with the same diagnosis on each admission. Instability of diagnosis occurred despite the fact that previous diagnoses were known and that only relatively few diagnoses contributed to this degree of chronicity. Schizophrenia and mania were the most stable diagnoses with considerable overlap between them. Organic disorders were a variable diagnosis, often made in the context of chronicity, substance abuse or uncertainty. A diagnosis of substance abuse usually occurred in the context of other comorbid diagnoses which sometimes took precedence. Instability of diagnosis will continue so long as the diagnostic system is based so heavily on clinical criteria.