PHQ-9
Also written as: PHQ-9 — Patient Health Questionnaire-9
A nine-item self-report questionnaire used to screen for and monitor depression severity.
Full Definition
The Patient Health Questionnaire-9 (PHQ-9) is a widely used depression screening and monitoring tool consisting of nine questions that correspond directly to the DSM criteria for major depressive disorder. Each item asks about symptoms experienced over the past two weeks and is scored from 0 (not at all) to 3 (nearly every day), with total scores ranging from 0 to 27. Scores of 5, 10, 15, and 20 represent mild, moderate, moderately severe, and severe depression thresholds, respectively. The PHQ-9 is valuable in both clinical practice and research for its brevity, validity, and ability to track symptom changes over time.
Usage
Usage note: Always include the hyphen and number. Distinguish from PHQ-2, which is a two-item screening version.
In Context
- "The patient's PHQ-9 score of 16 indicated moderately severe depression." — Screening assessment
- "Follow-up PHQ-9 scores showed significant improvement after eight weeks of treatment." — Progress monitoring