On Trends in the Diagnosis of Schizophrenia

A reexamination of hospital diagnoses made at New York State Psychiatric Institute in 1932–1941 and 1947–1956 (64 in each decade) indicated that the original diagnosticians used a broader concept of schizophrenia in the second decade (77 percent of the 64 cases) than in the first (28 percent). Rediagnoses by 16 American-trained psychiatrists showed practically no change between the decades (42 and 47 percent), while a British-trained psychiatrist rediagnosed more cases of schizophrenia in the first decade (31 percent) than in the second (19 percent). The authors believe these differences may be due to a decrease in the number of “hard-core” schizophrenics while the number of “ambiguous” schizophrenics increased, inviting more diagnoses of schizophrenia by those with a broader concept of schizophrenia.