The PHQ-9 is the most widely used depression screening tool in clinical practice. Nine questions, three minutes, and a clearer picture of where you stand.
Important: The PHQ-9 is a screening instrument, not a diagnostic tool. Only a qualified mental health professional can diagnose depression. If you're having thoughts of self-harm, please call 988 immediately.
Over the last 2 weeks, how often have you been bothered by the following problems?
9 questions · Takes about 3 minutes
The PHQ-9 (Patient Health Questionnaire-9) is the gold-standard depression screening tool used in clinical settings worldwide. It was developed in the late 1990s as part of the PRIME-MD diagnostic instrument and has since been validated in hundreds of studies across diverse populations.
The nine items map directly to the DSM-5 diagnostic criteria for Major Depressive Disorder: depressed mood, loss of interest, sleep changes, fatigue, appetite changes, guilt/worthlessness, concentration problems, psychomotor changes, and suicidal ideation.
Unlike many self-help quizzes, the PHQ-9 has strong psychometric properties. It has a sensitivity of 88% and specificity of 88% for detecting major depression at a cutoff score of 10. This means it's good at catching depression when it's present and good at not flagging it when it's not.
Each question maps to one of the nine diagnostic criteria for Major Depressive Disorder, covering mood, interest, sleep, energy, appetite, self-worth, concentration, psychomotor function, and suicidal ideation.
The 4-point response scale (0-3) measures symptom frequency over the past two weeks, not just presence/absence. This captures severity and creates a continuous score for tracking changes over time.
Scores map to five severity levels: minimal (0-4), mild (5-9), moderate (10-14), moderately severe (15-19), and severe (20-27). Each tier has distinct clinical implications and recommended actions.
The PHQ-9 was developed and validated by Kroenke, Spitzer, and Williams (2001) in a landmark study published in the Journal of General Internal Medicine. It has since been cited over 30,000 times and translated into over 80 languages.
The tool's nine questions correspond to the nine symptom criteria for Major Depressive Disorder in the DSM-5. Each question asks about symptom frequency over the past two weeks, using a 4-point scale from 'not at all' (0) to 'nearly every day' (3), producing scores from 0 to 27.
Research consistently shows the PHQ-9 is both reliable and valid across different clinical settings, age groups, and cultural contexts. A meta-analysis by Levis et al. (2019) in BMJ confirmed its diagnostic accuracy, particularly at the 10-point cutoff threshold.
The PHQ-9 is unique among screening tools because it can serve double duty: it screens for the presence of depression AND monitors treatment response over time. Many clinicians administer it at every visit to track whether treatment is working.
This tool is a screening instrument, not a diagnostic tool. Only a qualified mental health professional can diagnose depression. If you're having thoughts of self-harm, please contact 988 (Suicide & Crisis Lifeline) immediately.
Yes. The PHQ-9 (Patient Health Questionnaire-9) was developed by Drs. Robert Spitzer, Janet Williams, and Kurt Kroenke and is the most widely used depression screening tool in clinical practice worldwide. However, when taken online as a self-assessment, it's a screening tool — not a diagnosis.
Scores range from 0-27. 0-4 is minimal depression, 5-9 mild, 10-14 moderate, 15-19 moderately severe, and 20-27 severe. A score of 10 or above is the standard clinical threshold where providers typically recommend further evaluation.
Clinically, it's often administered at each appointment or monthly. For self-monitoring, every 2-4 weeks gives a useful picture of trends. The value is in tracking changes over time, not any single score.
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If you're having thoughts of self-harm, please reach out immediately: call 988 (Suicide & Crisis Lifeline), text HOME to 741741 (Crisis Text Line), or go to your nearest emergency room. These services are free, confidential, and available 24/7.
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