The PHQ-9 is a validated 9-item self-report tool for the severity of depressive symptoms, based directly on the DSM criteria for major depressive disorder. Scores range from 0 to 27, with severity bands from minimal to severe.
Scoring and severity bands
Each item is scored 0 ("not at all") to 3 ("nearly every day") over the past two weeks.
| Score | Severity | Clinical action |
|---|---|---|
| 0-4 | Minimal | Monitor |
| 5-9 | Mild | Watchful waiting |
| 10-14 | Moderate | Treatment plan |
| 15-19 | Moderately severe | Active treatment |
| 20-27 | Severe | Immediate evaluation |
When to administer it
Use the PHQ-9 at intake for a baseline, longitudinally to track response to treatment, and opportunistically whenever depression is suspected. Question 9 asks about thoughts of self-harm; any non-zero response warrants immediate follow-up.
Licensing
The PHQ-9 is free to use, copy, distribute, and translate without permission. It is in the public domain, and no license fee is required for clinical or research use.