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Phq 9 Depression Screening Calculator

Screen for depression instantly with the PHQ-9 calculator. Answer 9 symptom questions scored 0-3 and receive a total score with evidence-based severity interpretation.

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PHQ-9 Total Score (0-4 Minimal, 5-9 Mild, 10-14 Moderate, 15-19 Moderately Severe, 20-27 Severe)

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PHQ-9 Total Score (0-4 Minimal, 5-9 Mild, 10-14 Moderate, 15-19 Moderately Severe, 20-27 Severe)—points

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Understanding the PHQ-9 Depression Screening Calculator

The Patient Health Questionnaire-9 (PHQ-9) is a validated, nine-item self-report instrument used by clinicians worldwide to screen for, diagnose, and monitor the severity of major depressive disorder (MDD). Developed by Kroenke, Spitzer, and Williams and published in JAMA Internal Medicine, the PHQ-9 maps directly onto the nine DSM-5 diagnostic criteria for MDD, making it one of the most clinically grounded depression screeners available in primary care and mental health settings.

The PHQ-9 Scoring Formula

The total PHQ-9 score is computed by summing the ordinal response values across all nine items:

PHQ-9 Score = q1 + q2 + q3 + q4 + q5 + q6 + q7 + q8 + q9

Each question (qi) asks how often the respondent has been bothered by a specific symptom over the past two weeks. Responses follow a four-point Likert scale:

  • 0 — Not at all
  • 1 — Several days
  • 2 — More than half the days
  • 3 — Nearly every day

Total scores range from 0 to 27. Higher scores correspond to greater depression severity and a higher likelihood of a depressive disorder diagnosis.

Score Interpretation: Depression Severity Categories

Published clinical guidelines and statistical analysis plans for PHQ-9 trials define five standardized severity bands, as documented in the Statistical Analysis Plan for PHQ-9 Total Score Categories (ClinicalTrials.gov):

  • 0–4: None to minimal depression — routine monitoring; no immediate intervention typically required
  • 5–9: Mild depression — watchful waiting; repeat PHQ-9 at follow-up visit
  • 10–14: Moderate depression — formal treatment plan discussion; counseling or pharmacotherapy considered
  • 15–19: Moderately severe depression — active treatment with antidepressants and/or structured psychotherapy
  • 20–27: Severe depression — immediate referral to psychiatric care; combination therapy warranted

A score of 10 or higher is the standard clinical threshold for probable MDD, with approximately 88% sensitivity and 88% specificity at this cut-point, as outlined by the NCBI Calculation of Harmonized Depression Outcome Measures.

The Nine PHQ-9 Variables Explained

Each item corresponds directly to a core DSM-5 criterion for major depressive disorder:

  • Q1 — Anhedonia: Little interest or pleasure in doing things. Along with depressed mood, anhedonia is one of two cardinal symptoms required for an MDD diagnosis.
  • Q2 — Depressed Mood: Feeling down, depressed, or hopeless — the second essential criterion for MDD.
  • Q3 — Sleep Disturbance: Trouble falling or staying asleep, or sleeping too much (hypersomnia). Sleep disruption appears in nearly all presentations of MDD.
  • Q4 — Fatigue: Feeling tired or having little energy. Fatigue is among the most frequently reported MDD symptoms in primary care populations.
  • Q5 — Appetite and Weight Changes: Poor appetite or overeating, which can produce clinically significant weight loss or gain over weeks.
  • Q6 — Low Self-Worth or Guilt: Feeling bad about oneself, or that one is a failure, or has let family down — reflecting the guilt and worthlessness criterion of DSM-5.
  • Q7 — Concentration Difficulty: Trouble concentrating on tasks such as reading or watching television, impairing daily functioning.
  • Q8 — Psychomotor Changes: Moving or speaking so slowly others notice, or being so fidgety or restless that movement is markedly increased — observable psychomotor agitation or retardation.
  • Q9 — Suicidal Ideation: Thoughts of being better off dead or of hurting oneself. Any score above 0 on Q9 requires immediate clinical attention and safety assessment.

Worked Calculation Example

A patient reports the following responses over the past two weeks: Q1=1, Q2=2, Q3=2, Q4=3, Q5=1, Q6=1, Q7=2, Q8=0, Q9=0. The total PHQ-9 score equals 1+2+2+3+1+1+2+0+0 = 12, placing this individual in the moderate depression range (10–14). This score warrants a structured treatment plan discussion with a licensed healthcare provider, typically including psychotherapy referral and consideration of antidepressant medication.

Clinical Use Cases and Limitations

The PHQ-9 supports three primary clinical functions: initial population screening, differential diagnosis assistance, and longitudinal treatment monitoring. A decrease of 5 or more points between administrations is the widely accepted minimum clinically important difference indicating a meaningful therapeutic response. Item-response modeling research published in PMC (GAD-7 and PHQ-8 Mathematical Patterns) confirms the strong internal consistency and scaling properties shared across PHQ family instruments. The PHQ-9 has been validated in over 8,000 patients across primary care and specialty settings. Despite these strengths, the PHQ-9 is a screening tool, not a standalone diagnostic instrument. It does not account for medical conditions (e.g., hypothyroidism) that can mimic depressive symptoms, and it must always be interpreted within a broader clinical evaluation by a qualified professional.

Crisis Resources

If Q9 receives any score above 0, or if there is any concern about immediate safety, contact emergency services or call and text 988 (Suicide and Crisis Lifeline, USA) — available 24 hours a day, 7 days a week.

Reference

Frequently asked questions

What is the PHQ-9 and how does the depression PHQ calculator work?
The PHQ-9 (Patient Health Questionnaire-9) is a validated 9-item self-report screening tool for major depressive disorder. The depression PHQ calculator sums responses scored 0 (not at all) to 3 (nearly every day) across nine DSM-5-aligned symptom questions, producing a total score between 0 and 27. Higher scores indicate greater depression severity, and a score of 10 or above suggests clinically significant depression that warrants professional evaluation and possible treatment.
What do different PHQ-9 scores mean in terms of depression severity?
PHQ-9 scores map to five clinically recognized severity bands: 0-4 indicates none to minimal depression; 5-9 indicates mild depression; 10-14 indicates moderate depression; 15-19 indicates moderately severe depression; and 20-27 indicates severe depression. These categories directly guide clinical decision-making — from watchful waiting at lower scores to immediate psychiatric referral at scores of 20 or above. A score of 10 carries approximately 88% sensitivity and 88% specificity for major depressive disorder.
How often should a person complete the PHQ-9 depression screening calculator?
For individuals already in treatment, clinicians typically readminister the PHQ-9 every 2 to 4 weeks to track treatment response over time. A reduction of 5 or more points between assessments is considered the minimum clinically important difference, indicating meaningful improvement. For general preventive care, the PHQ-9 is commonly administered at annual wellness visits or whenever a patient presents with mood-related concerns. The appropriate retesting frequency should always be determined by a licensed healthcare provider.
Is the PHQ-9 depression PHQ calculator a substitute for a professional diagnosis?
No — the PHQ-9 is a screening and monitoring instrument, not a diagnostic tool. A high score strongly suggests that a formal clinical evaluation is warranted, but diagnosing major depressive disorder requires a comprehensive assessment by a licensed mental health professional or physician. The calculator quantifies symptom burden and tracks changes over time, but it cannot account for medical comorbidities, medication effects, or contextual factors that only a structured clinical interview can assess.
What should someone do after getting a high score on the PHQ-9 calculator?
Anyone scoring 10 or above should schedule an appointment with a primary care physician, psychiatrist, or licensed therapist as soon as possible. Scores of 15 or higher indicate moderately severe to severe depression and suggest an urgent need for professional support, which may include antidepressant medication, structured psychotherapy, or both. If Q9 — the question about thoughts of self-harm or being better off dead — receives any score above 0, the individual should contact emergency services or call and text 988 (Suicide and Crisis Lifeline) immediately, available 24 hours a day, 7 days a week.
How accurate and reliable is the PHQ-9 for detecting depression?
The PHQ-9 demonstrates strong psychometric properties across diverse clinical populations. At the standard cut-point of 10, studies report sensitivity and specificity both at approximately 88% for detecting major depressive disorder. Internal consistency is high, with Cronbach's alpha values typically exceeding 0.80 across validated studies. Research published by NCBI and in peer-reviewed psychiatric journals confirms the tool has been rigorously tested in over 8,000 patients across primary care and specialty settings, establishing it as one of the most evidence-supported depression screeners available.