Screen for depression using the PHQ-9 questionnaire. Score severity, get treatment recommendations, and track symptoms over time with this validated tool.
The PHQ-9 (Patient Health Questionnaire-9) Calculator is the most widely used validated screening instrument for depression worldwide. Developed by Drs. Kroenke, Spitzer, and Williams in 2001, the PHQ-9 assesses each of the nine DSM-5 criteria for major depressive disorder on a 0–3 frequency scale over the past two weeks, yielding a total score of 0–27.
Depression affects approximately 280 million people globally and is the leading cause of disability worldwide. Despite effective treatments being available, fewer than half of those affected receive adequate treatment — often because depression goes unrecognized. The PHQ-9 provides a brief, validated tool for screening, severity assessment, and treatment monitoring that can be administered in under 3 minutes.
This calculator scores all nine PHQ-9 items, classifies depression severity, provides treatment recommendations based on current clinical guidelines, identifies suicide risk (item 9), and breaks down symptoms into somatic and cognitive domains. It should be used as a screening tool — not a diagnostic one — and positive screens require clinical confirmation through a structured diagnostic interview.
Depression is common, disabling, and treatable — but often unrecognized. The PHQ-9 is free, validated in 80+ languages, takes under 3 minutes, and has 88% sensitivity and 88% specificity for major depression at a cutoff of 10. Serial scoring (every 2–4 weeks) tracks treatment response: a 50% reduction in score indicates clinically meaningful improvement.
PHQ-9 Score = Sum of 9 items (each scored 0–3) Total range: 0–27 Severity: • 0–4: Minimal / None • 5–9: Mild • 10–14: Moderate • 15–19: Moderately Severe • 20–27: Severe Sensitivity: 88%, Specificity: 88% at score ≥10 Positive predictive value: ~50% in primary care
Result: PHQ-9 Score: 10 — Moderate Depression
Total score of 10 falls at the threshold for moderate depression. Treatment plan recommended: consider psychotherapy (CBT or IPT) and/or antidepressant initiation. Somatic symptoms (5/12) and cognitive symptoms (5/12) are balanced, suggesting mixed presentation. No suicidal ideation endorsed.
The PHQ-9 is the most widely used depression screening instrument in the world, validated in over 80 languages across diverse populations including primary care, specialty clinics, emergency departments, and obstetric settings. Its brevity (under 3 minutes to administer), free availability (no licensing fees), and strong psychometric properties have made it the standard of care for depression screening and monitoring.
Serial PHQ-9 scores are more valuable than a single assessment. A drop of 5+ points is considered a clinically meaningful response. A 50% reduction from baseline indicates treatment response. Achieving a score of ≤4 (remission) is the treatment goal. If scores plateau after 4–6 weeks of treatment, consider augmentation, switching medications, or adding psychotherapy.
Depression rarely occurs in isolation. Over 60% of depressed patients have comorbid anxiety (screen with GAD-7), 30% have substance use disorders (screen with AUDIT/DASI), and chronic medical conditions (diabetes, heart disease, chronic pain) multiply depression risk 2–3×. A comprehensive assessment including the PHQ-9 alongside other validated screeners provides a fuller picture of mental health needs.
The PHQ-9 is a 9-item self-report questionnaire that screens for major depressive disorder by assessing the frequency of each DSM-5 depression criterion over the past 2 weeks. Each item scores 0–3, yielding a total of 0–27. It was developed and validated by Drs. Kroenke, Spitzer, and Williams in 2001 and is used in over 100 countries.
No — the PHQ-9 is a screening tool, not a diagnostic instrument. A positive screen (score ≥10) indicates a high probability of major depressive disorder but requires confirmation through a clinical interview (e.g., SCID, MINI, or clinical assessment). The positive predictive value in primary care is approximately 50%, meaning half of positive screens will have confirmed depression on clinical evaluation.
Guidelines vary, but generally: score 10–14 (moderate) warrants treatment consideration (therapy and/or medication). Score 15+ (moderately severe to severe) strongly recommends active treatment with both medication and psychotherapy. Score 5–9 (mild) suggests watchful waiting with repeat screening in 2 weeks. These are guidelines — clinical judgment considers context, functional impairment, and patient preferences.
For moderate depression, psychotherapy (particularly CBT and IPT) and antidepressant medication have similar efficacy (~60% response rate). Combination therapy (medication + psychotherapy) is significantly more effective than either alone, particularly for severe depression, with response rates of 70–80%. Exercise, sleep optimization, and social support are important adjunctive treatments.
For treatment monitoring: every 2–4 weeks until remission (score ≤4), then every 3–6 months during continuation therapy. For screening: at least annually in primary care, and on initial visits with a mental health provider. More frequent screening for high-risk populations (chronic illness, substance use, postpartum, history of depression).
Any endorsement of item 9 (thoughts of death or self-harm) should be taken seriously. If you are having thoughts of suicide: call or text 988 (Suicide & Crisis Lifeline), text HOME to 741741 (Crisis Text Line), or go to the nearest emergency department. You can also discuss these thoughts with your doctor or therapist — having fleeting thoughts does not mean you will act on them, but professional evaluation is essential.