Risk Rates for Depression

To the Editor.— I read with great interest the recent report in this journal of an elegant, controlled epidemiologic study on familial risk rates for depression by Weissman et al.¹The inclusion of a control group and the comparison of control and high-risk relatives by similar case-finding and diagnostic methods is a model of careful research in this important area. Nevertheless, the report raised some intriguing questions about the state of knowledge of the epidemiology of affective disorders that may be of general interest. Weissman et al¹reported that the prevalence rate of major depression (evidently not age corrected to account for lifetime morbid risk) among firstdegree relatives (of either sex) of severely depressed probands was approximately 14.2%. In contrast, the comparable rate in a carefully screened normal control population was about 4.5%, to yield a risk ratio 3.2 x as high among relatives of depressed persons. The comparable