Psychiatric epidemiology: progress and prospects in the year 2000.

In the last half century, the field of psychiatric epidemiology has been born and is rapidly coming of age. The emergence of chronic disease epidemiology in the 1940s and 1950s was conceptually joined to the revival of interest in psychiatric disorders that came about after World War II, in a publication by the Milbank Memorial Fund, in 1950, which used the term psychiatric epidemiology (1). For 25 years following, sometimes called the "second generation" of psychiatric epidemiology (2), the field was dominated by sociologists and social psychiatrists, who applied newly developed household survey techniques to the problem of estimation of the prevalence of mental problems and who studied causal factors such as socioconomic stratification (3, 4), social integration (5), and social stress (6). There were relatively few epidemiologic studies of specific mental disorders, and those that existed focused efforts on measuring the extent of disorders in the population, that is, descriptive epidemiology (7). Research directed toward understanding the etiology of disorders— analytic epidemiology—used measures of psychological distress or global impairment, precluding integration with laboratory and clinical research and hindering construction of credible etiologic hypotheses. During this second generation of psychiatric epidemiology, there were developments in related fields that were to overtake and change the field drastically. One important advance was the development of the empirical basis for psychiatric diagnosis. In the latter half of the decade of the 1960s and into the 1970s, several studies (8, 9) showed that the reliability of psychiatric diagnosis was so weak as to allow the charge that diagnoses were "myths" or "ideology" (10,11). Empirical work on