PHQ-9 calculator online: depression screening and severity questionnaire
PHQ-9 is a 9-item depression screening and severity questionnaire. Each item scored 0–3, total 0–27. Interpretation per DSM-5: none, mild, moderate, moderately severe, severe depression. Used in primary care and patients with chronic conditions.
PHQ-9 is a screening tool, not a diagnostic instrument. Results do not replace clinical assessment by a specialist.
About this calculator
PHQ-9 (Patient Health Questionnaire-9) is a 9-item self-report tool validated for screening and severity assessment of major depressive episode in primary care. Developed by Spitzer, Kroenke, and Williams in 1999 from DSM-IV criteria (still applicable to DSM-5). Each item maps to one major depressive episode criterion: anhedonia, depressed mood, sleep disturbance, fatigue, appetite change, worthlessness, concentration impairment, psychomotor agitation or retardation, suicidal ideation. Items are rated 0 (not at all) to 3 (nearly every day), total 0–27. Interpretation: 0–4 – none, 5–9 – mild, 10–14 – moderate, 15–19 – moderately severe, 20–27 – severe. A score ≥10 has 88% sensitivity and specificity for major depression. Used in primary care, psychiatry, neurology, and chronic disease populations. Item 9 (suicidal ideation) requires immediate clinical evaluation if positive. The questionnaire does not replace clinical diagnosis but supports routine screening.
Source
Formula version: kroenke-2001-v1
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