The Patient Health Questionnaire-9, or PHQ-9, is a nine-question self-report scale used around the world in clinics and research to screen for depression and track changes in symptoms.
What does it ask?
Each of the nine questions matches one of the symptoms of major depression, including low mood, loss of interest or pleasure, sleep changes, tiredness, appetite changes, feeling bad about yourself, difficulty concentrating, slowed or restless movement, and thoughts of being better off dead or of self-harm. For each, you say how often it has bothered you over the last two weeks, from "not at all" to "nearly every day".
How is it scored?
Each answer scores from 0 to 3, so the total runs from 0 to 27. Published guidance groups totals into bands ranging from minimal to severe symptoms. Higher totals mean more frequent symptoms. The last question, about self-harm thoughts, deserves attention even if your total is low.
Screening is not diagnosis
A screening tool asks whether symptoms are present and how often. It does not tell you why. Low mood can come from depression, but also from grief, medical conditions, thyroid problems, medication, sleep loss or burnout. A clinician will ask about your history, how long symptoms have lasted and how much they affect your life before reaching a diagnosis.
Why the PHQ-9 is widely used
- It is short and takes only a few minutes.
- It is based on the symptom criteria clinicians use.
- It can be repeated over time to see whether symptoms are improving.
- Its shorter sibling, the PHQ-2, is a quick two-question first check.
Other depression scales
The CES-D is common in research, the Geriatric Depression Scale is designed for older adults, and the DASS-21 measures depression together with anxiety and stress. You can take them all on our depression test page.
If you are struggling
Please speak with a doctor or a qualified mental-health professional. If you have thoughts of harming yourself, tell someone you trust and get help right away. In India you can call Tele-MANAS at 14416, a free government mental-health helpline. If you are in immediate danger, contact your local emergency services.