Abstract
While most patients with recognized depressive illness are treated by general practitioners without referral, there is evidence that many patients classifiable as depressed after psychiatric interview are not diagnosed as such. Missing depression is of great importance since it is now eminently treatable. This paper explores the use in primary care of questionnaire tests for depression and also their role in case finding in vulnerable groups of patients. The potential of existing validated questionnaires in clinical work and audit is largely unexploited. As yet, however, there is no gold standard for the diagnosis of depression seen in primary care. Clusters of symptoms do not yet accurately predict the course of the illness or response to treatment. More research is needed on the natural history of depression seen in the community, as well as on treatment and outcome.