Depression (PHQ-9)
Calculate your PHQ-9 depression screening score using the standardized Patient Health Questionnaire-9 with 9 symptom questions, severity interpretation, and clinical management recommendations.
About This Calculator
The PHQ-9 (Patient Health Questionnaire-9) calculator helps assess depression severity using the most widely validated and commonly used depression screening tool in clinical practice worldwide. Developed by Drs. Spitzer, Kroenke, and Williams in 2001, the PHQ-9 directly maps to the nine DSM-5 diagnostic criteria for major depressive disorder (MDD): anhedonia, depressed mood, sleep disturbance, fatigue, appetite changes, feelings of worthlessness or guilt, concentration difficulties, psychomotor changes, and suicidal ideation.
The PHQ-9 has been validated across diverse healthcare settings including primary care, obstetrics-gynecology, and mental health specialties, with over 6,000 patients in the original validation study. It demonstrates excellent psychometric properties with a sensitivity of 88% and specificity of 88% for major depressive disorder at the standard cutoff score of 10. The questionnaire takes approximately 3-5 minutes to complete, making it efficient for routine screening in busy clinical environments.
Each of the 9 items is scored from 0 (not at all) to 3 (nearly every day), measuring how often the patient has been bothered by each symptom over the past two weeks. Total scores range from 0-27, with higher scores indicating greater depression severity. A response of 1 or higher on question 9 (suicidal thoughts) requires immediate clinical attention and suicide risk assessment regardless of the total score.
Beyond initial screening, the PHQ-9 is widely used to monitor treatment response over time. A clinically significant improvement is defined as a reduction of 5 or more points, and remission is typically defined as a score below 5. The scale is freely available in the public domain and has been translated into over 80 languages.
Regional Notes
United States: The USPSTF recommends depression screening for all adults aged 18+ using validated instruments like the PHQ-9. The PHQ-2 (first 2 items) is sometimes used as an ultra-brief initial screener, with the full PHQ-9 administered if the PHQ-2 is positive. Medicare and most insurance plans cover annual depression screening. Crisis resources: National Suicide Prevention Lifeline 988.
United Kingdom: NICE guidelines (CG123) recommend the PHQ-9 for initial assessment of depression severity in primary care. It is used alongside the GAD-7 for anxiety screening. Treatment follows a stepped-care model based on severity. Crisis resources: Samaritans 116 123.
India: The National Mental Health Programme (NMHP) and District Mental Health Programme (DMHP) increasingly use the PHQ-9 for depression screening at the primary care level. Hindi and other regional language translations are available. Access to mental health specialists remains limited, with fewer than 0.75 psychiatrists per 100,000 population in many states. Crisis resources: iCall 9152987821, Vandrevala Foundation 1860-2662-345.
Frequently Asked Questions
What is the PHQ-9 and what does it measure?
The PHQ-9 (Patient Health Questionnaire-9) is a validated 9-item self-administered screening tool that measures the severity of depressive symptoms over the past two weeks. Each item corresponds to one of the DSM-5 diagnostic criteria for major depressive disorder (MDD), scored from 0 (not at all) to 3 (nearly every day), yielding a total score range of 0 to 27.
How is the PHQ-9 score interpreted for depression severity?
The PHQ-9 total score is interpreted as follows: 0-4 indicates minimal or no depression (monitor, no treatment typically needed). 5-9 indicates mild depression (clinical judgment needed). 10-14 indicates moderate depression (active treatment warranted). 15-19 indicates moderately severe depression (pharmacotherapy and psychotherapy strongly indicated). 20-27 indicates severe depression (immediate active treatment required, consider psychiatric referral).
Is a positive PHQ-9 score sufficient for diagnosing depression?
No. The PHQ-9 is a screening tool, not a diagnostic instrument. A final diagnosis of major depressive disorder requires a clinical interview and mental status examination, including assessment of functional impairment, symptom duration, and ruling out bipolar disorder, normal bereavement, and medical conditions that can cause depressive symptoms. The PHQ-9 helps objectify depression severity but should not be used alone for diagnosis.
What should I do if I scored high on the PHQ-9 or endorsed the self-harm question?
If you scored in the moderate to severe range (10+), consult a healthcare professional for a comprehensive evaluation. A positive response to question 9 (thoughts of self-harm or suicide) warrants immediate clinical attention and suicide risk assessment. If you are having thoughts of harming yourself, contact a crisis helpline immediately: National Suicide Prevention Lifeline (US): 988, Samaritans (UK): 116 123, iCall (India): 9152987821.
What treatments are effective for depression based on PHQ-9 severity?
Treatment depends on depression severity. For mild depression (5-9), supportive counseling, lifestyle modifications, and monitoring may suffice. For moderate depression (10-14), evidence-based treatments include SSRIs (sertraline, fluoxetine, escitalopram) and psychotherapy such as cognitive behavioral therapy (CBT). For moderately severe to severe depression (15-27), a combination of antidepressant medication and intensive psychotherapy is recommended, with psychiatric referral for severe cases.
Who developed the PHQ-9 and how is it validated?
The PHQ-9 was developed by Drs. Robert Spitzer, Kurt Kroenke, and Janet B.W. Williams in 2001 as part of the Patient Health Questionnaire (PHQ) family. It was validated in a study of 6,000 patients across 8 primary care and 7 obstetrics-gynecology clinics. The PHQ-9 has demonstrated excellent internal reliability (Cronbach alpha of 0.86-0.89) and test-retest reliability, with a sensitivity of 88% and specificity of 88% for major depressive disorder at a cutoff score of 10.
Can the PHQ-9 be used to monitor treatment response over time?
Yes. The PHQ-9 is widely used to monitor treatment response in patients undergoing depression treatment. A clinically meaningful improvement is typically defined as a reduction of 5 or more points from baseline. The scale can be administered at each follow-up visit (typically every 2-4 weeks during acute treatment) to track symptom changes and guide treatment decisions. Remission is often defined as a PHQ-9 score below 5.
What are the differences in depression screening guidelines between the US, UK, and India?
In the US, the USPSTF recommends depression screening for all adults aged 18 and older using validated instruments like the PHQ-9, with adequate systems in place for follow-up. In the UK, NICE guidelines recommend using the PHQ-9 for initial assessment and monitoring of depression severity in primary care. In India, the National Mental Health Programme (NMHP) increasingly incorporates PHQ-9 screening at the primary care level, though access to mental health specialists remains limited in rural areas.