The General Health Questionnaire and the detection of emotional disorder by General Practitioners. A replicated study

This paper reports on a study of psychiatric morbidity in 920 patients attending 18 General Practitioners in Lewisham, South East London. Two indices of morbidity were computed on the basis of the patients responses to the General Health Questionnaire (GHQ) and the GPs' own estimates. Indices of the GPs' detection ability were found by comparing questionnaire and GP rating. The results are compared to those obtained by other workers in a sample of Manchester GPs. The GHQ gave a prevalence estimate of 42.9% which is comparable to that of 39.6% obtained in the Manchester study. In addition, the variation in caseness across sociodemographic groups was consistent with the Manchester findings. The GPs' estimates of morbidity, while much lower than those obtained in Manchester, have similar sociodemographic profiles. The results support the use of the GHQ as a screening device in epidemiological studies, and suggest the need for further investigation of the individual GP's performance as a case detector.