Prevalence of specific psychiatric disorders in an urban primary care setting

In a two-stage epidemiological study to determine the prevalence and pattern of psychiatric morbidity in an urban primary care setting in Nigeria, the 12-item General Health Questionnaire (GHQ) was used to screen 787 clinic attenders while a modified version of a structured clinical interview designed for epidemiological surveys, the Composite International Diagnostic Interview (CIDI), was used to interview 214 subjects in the second stage. In order to improve case detection, selection for the second-stage was by stratified sampling in which patients were selected using a low score threshold and a revised scoring method devised to improve screening ability. A weighted prevalence for specific DSM-IIIR diagnoses of 27.8 per cent was obtained. Another 7.3 per cent of the clinic attenders suffered from non-specific disorders principally with mixed affective symptomatology. The association of demographic features to the disorders was examined; while a number of the associations followed previously reported trends, a few were unusual, possibly reflecting the cultural differences in the various study environments.