Screening for depression in the Serbian general population sample: an alternative to the traditional patient health questionnaire-9 cut-off score.

Abstract

The Patient Health Questionnaire (PHQ-9) score≥10 balances best sensitivity and specificity when detecting probable depression in patients. In the general population, different cut-offs are suggested. European studies on general populations validating the PHQ-9 against a diagnostic interview to detect depression are rare. This was a cross-sectional observational epidemiological survey using multistage household probabilistic sampling to recruit a representative adult sample (N=1203; age=43.7±13.6; 48.7% male). Mental disorders including current major depressive episode (MDE) were observer-rated (Mini International Neuropsychiatric Interview). The PHQ-9, quality of life (QoL), and loneliness were self-assessed. We performed validity and reliability tests of the PHQ-9 and receiver operating curve (ROC) analysis. The Serbian PHQ-9 was internally consistent and correlated in the expected directions with QoL and loneliness. At the cut-off score≥8, sensitivity was .85 and specificity was .91. ROC analysis showed that the area under the curve was .95, indicating that the Serbian PHQ-9 can discriminate very well between persons with/without MDE. When the PHQ-9 is assessed against the structured diagnostic interview in the general population to detect depression, the cut-off of ≥8 balances best sensitivity and specificity.