June 1974

Validity of the Diagnosis of Primary Affective DisorderA Prospective Study With a Five-Year Follow-up

Author Affiliations

St. Louis
From the Department of Psychiatry, Washington University School of Medicine, St. Louis.

Arch Gen Psychiatry. 1974;30(6):751-756. doi:10.1001/archpsyc.1974.01760120017003

In a five-year prospective follow-up study of 115 psychiatrically hospitalized patients, interinterview reliability for depressive symptoms was 94%. Specific interrater diagnostic reliability was 80%, using explicit diagnostic criteria. Disagreement was solely on degree of certainty within a specific diagnosis, not between different diagnoses. Interrater reliability was 100% for presence or absence of affective disorder.

Follow-up was blind. Of 52 patients initially diagnosed by explicit criteria as having primary affective disorder, 43 were followed up. Blind diagnostic agreement was 86%. An additional 9% not concordant by blind diagnosis fell within the usual clinical concept of primary affective disorder. Only two patients (5%) had a course incompatible with the natural history of primary affective disorder. To our knowledge this is the first blind, prospective validation of criteria for the diagnosis of primary affective disorder.