PHQ-9 Depression Assessment

PHQ-9 Calculator - Patient Health Questionnaire for Depression Screening

The Patient Health Questionnaire-9 (PHQ-9) is a validated, widely-used depression screening and severity assessment tool that consists of nine questions directly corresponding to the DSM criteria for major depressive disorder. This self-administered questionnaire asks patients to rate how often they have been bothered by symptoms including depressed mood, anhedonia, sleep disturbances, fatigue, appetite changes, feelings of worthlessness, concentration difficulties, psychomotor changes, and suicidal ideation over the past two weeks. Each item is scored from 0 (not at all) to 3 (nearly every day), generating a total score ranging from 0 to 27 that indicates depression severity: minimal (0-4), mild (5-9), moderate (10-14), moderately severe (15-19), and severe (20-27) depression. The PHQ-9 serves dual purposes as both a diagnostic screening tool and a measure for monitoring treatment response over time. Healthcare providers across specialties use the PHQ-9 for routine depression screening, particularly in primary care settings where mental health concerns often present alongside medical complaints. The tool's brief, standardized format enables systematic depression detection, facilitates treatment initiation, and provides objective metrics for tracking symptom improvement during therapy. Importantly, item 9 specifically assesses suicidal ideation, alerting clinicians to patients requiring immediate safety evaluation.