Phq 9 Depression Score Calculator
Calculate your Phq 9 Depression Score by entering grades and credit hours. Get weighted GPA, letter grade equivalents, and improvement targets.
Formula
PHQ-9 Total = Sum of Q1 through Q9 (each 0-3) | Range: 0-27
The PHQ-9 scores nine DSM criteria for depression on a 0-3 scale based on frequency over the past two weeks. Total scores map to severity: 0-4 minimal, 5-9 mild, 10-14 moderate, 15-19 moderately severe, 20-27 severe.
Worked Examples
Example 1: Mild Depression Screening
Problem: A patient scores: Q1=1, Q2=1, Q3=2, Q4=1, Q5=0, Q6=1, Q7=1, Q8=0, Q9=0. Interpret the result.
Solution: Total score: 1+1+2+1+0+1+1+0+0 = 7\nSeverity: Mild Depression (5-9 range)\nSomatic subscale: Q3+Q4+Q5+Q8 = 2+1+0+0 = 3/12\nCognitive subscale: Q1+Q2+Q6+Q7+Q9 = 1+1+1+1+0 = 4/15\nQ9 (self-harm): 0 — No safety concern\nRecommendation: Watchful waiting, repeat in 2-4 weeks
Result: PHQ-9 = 7 | Mild Depression | Watchful waiting recommended
Example 2: Treatment Response Monitoring
Problem: A patient on antidepressants had baseline PHQ-9 of 18. After 6 weeks, scores: Q1=1, Q2=1, Q3=1, Q4=2, Q5=1, Q6=1, Q7=0, Q8=1, Q9=0.
Solution: New total: 1+1+1+2+1+1+0+1+0 = 8\nBaseline: 18 (Moderately Severe)\nCurrent: 8 (Mild)\nChange: -10 points (>5 = clinically significant response)\nQ9 improved from prior positive to 0\nRecommendation: Treatment is working, continue current regimen
Result: PHQ-9 dropped from 18 to 8 | 10-point improvement | Treatment response confirmed
Frequently Asked Questions
What is the PHQ-9 and how is it used clinically?
The Patient Health Questionnaire-9 (PHQ-9) is a widely validated, self-administered screening tool for major depressive disorder. Developed by Drs. Robert Spitzer, Janet Williams, and Kurt Kroenke in 1999, it is based directly on the nine diagnostic criteria for major depression from the DSM (Diagnostic and Statistical Manual of Mental Disorders). Each question is scored from 0 to 3, yielding a total between 0 and 27. Clinicians use it for initial screening, monitoring treatment response over time, and measuring depression severity. It is used in primary care, mental health settings, research studies, and even occupational health assessments worldwide. The PHQ-9 takes approximately two minutes to complete.
What do the PHQ-9 score ranges mean?
The PHQ-9 score is interpreted across five severity ranges. A score of 0 to 4 indicates minimal depression symptoms that generally do not require treatment. Scores of 5 to 9 suggest mild depression where watchful waiting and lifestyle modifications may be appropriate. Moderate depression falls in the 10 to 14 range, where counseling or medication should be considered. Moderately severe depression, scored 15 to 19, typically warrants active treatment with antidepressants and psychotherapy. Severe depression is indicated by scores of 20 to 27 and calls for immediate treatment initiation, often combining medication with therapy and possibly specialist referral. A score of 10 or higher is commonly used as the clinical cutoff for major depression.
How accurate is the PHQ-9 for diagnosing depression?
The PHQ-9 has been extensively validated across diverse populations and settings. At the standard cutoff score of 10, it demonstrates a sensitivity of 88 percent and specificity of 88 percent for detecting major depressive disorder. This means it correctly identifies 88 percent of people with depression and correctly rules out 88 percent of people without depression. However, the PHQ-9 is a screening tool, not a diagnostic instrument. A positive screen should be followed by a clinical interview to confirm diagnosis, assess for comorbid conditions, evaluate suicide risk, and rule out other causes of symptoms such as thyroid disorders, medication side effects, or substance use. The PHQ-9 is most valuable when used longitudinally to track symptom changes over time.
How often should the PHQ-9 be administered for monitoring?
For treatment monitoring, the PHQ-9 should ideally be administered at each clinical visit, typically every two to four weeks during active treatment. A reduction of 5 or more points from the baseline score is considered a clinically meaningful response to treatment, while a score below 5 indicates remission. If starting antidepressant medication, reassessment at four to six weeks helps determine if the medication is effective. For patients in remission, quarterly reassessment during the continuation phase of treatment helps detect early relapse. In primary care screening settings, annual screening is recommended for adults by many clinical guidelines. Tracking scores over time provides an objective measure of progress that complements clinical observation and patient self-report.
Is my data stored or sent to a server?
No. All calculations run entirely in your browser using JavaScript. No data you enter is ever transmitted to any server or stored anywhere. Your inputs remain completely private.
What formula does Phq 9 Depression Score Calculator use?
The formula used is described in the Formula section on this page. It is based on widely accepted standards in the relevant field. If you need a specific reference or citation, the References section provides links to authoritative sources.