PHQ-9
Also written as: PHQ-9 — Patient Health Questionnaire-9
Nine-item self-report scale measuring depression severity based on DSM criteria.
Full Definition
The Patient Health Questionnaire-9 is a widely used depression screening and severity assessment tool that corresponds directly to the nine DSM criteria for major depressive disorder. Each item is rated on a scale 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 includes a question about functional impairment and can be used for screening, diagnosis, monitoring treatment response, and measuring depression severity over time.
Usage
Usage note: Include specific score when documenting; distinguish from PHQ-2; useful for tracking treatment progress.
In Context
- "The patient's PHQ-9 score decreased from 18 to 8 over six weeks of antidepressant treatment." — Progress monitoring note
- "PHQ-9 screening at intake revealed a score of 15, indicating moderately severe depression." — Initial assessment summary