Screening for depression.

In the United States, depression affects up to 9 percent of patients and accounts for more than $43 billion in medical care costs. The U.S. Preventive Services Task Force recommends screening in adolescents and adults in clinical practices that have systems in place to ensure accurate diagnosis, effective treatment, and follow-up. It does not recommend for or against screening for depression in children seven to 11 years of age or screening for suicide risk in the general population. The Patient Health Questionnaire (PHQ)-2 and PHQ-9 are commonly used and validated screening tools. The PHQ-2 has a 97 percent sensitivity and 67 percent specificity in adults, whereas the PHQ-9 has a 61 percent sensitivity and 94 percent specificity in adults. If the PHQ-2 is positive for depression, the PHQ-9 should be administered; in older adults, the 15-item Geriatric Depression Scale is also an appropriate follow-up test. If these screening tests are positive for depression, further evaluation is needed to confirm that the patient's symptoms meet the Diagnostic and Statistical Manual of Mental Disorders' criteria for diagnosis.