Most adults with clinically significant depression visit a primary care physician rather than a psychiatrist [1-3], and the diagnosis is missed in a substantial number of depressed primary care patients. A meta-analysis of 41 studies (n >50,000 primary care patients) found that among all of the patients with a depressive disorder, the general practitioners identified depression in approximately 50 percent . Another meta-analysis (36 studies) found that nonpsychiatric physicians did not diagnose depression in over 50 percent of their depressed patients . In addition, primary care clinicians may over-diagnose depression in patients who do not have a depressive disorder; meta-analyses estimate that the rate of false positives is 15 to 20 percent [4,5]. However, these findings should be interpreted with recognition of the primary care approach to diagnosis over several office visits, the complexity of diagnosing depression in the context of chronic general medical illnesses, and that depressed patients who present to primary care practices may be less severely ill than patients who present to psychiatric practices.
This topic reviews the assessment and diagnosis of depression in adults. The clinical features, epidemiology, neurobiology, treatment, and prognosis of depression in adults are discussed separately, as are the clinical features and diagnosis of depression in pediatric and elderly patients:
●(See "Unipolar depression in adults: Clinical features".)
●(See "Unipolar depression in adults: Epidemiology, pathogenesis, and neurobiology".)
●(See "Unipolar major depression in adults: Choosing initial treatment".)