PHQ-9 Score Thresholds for Psychiatric Evaluation
Patients with a PHQ-9 score of 15 or higher (moderately severe to severe depression) require referral to psychology/psychiatry for diagnosis and treatment. 1
PHQ-9 Score-Based Intervention Guidelines
The PHQ-9 is a validated tool for depression screening and severity assessment with specific score thresholds that guide clinical decision-making:
| PHQ-9 Score | Severity Category | Recommended Intervention |
|---|---|---|
| 1-7 | None/Mild | No intervention required; patient likely has effective coping skills |
| 8-14 | Moderate | Seek consultation with psychology/psychiatry; consider low-intensity interventions |
| 15-19 | Moderately Severe | Referral to psychology/psychiatry for diagnosis and treatment |
| 20-27 | Severe | Urgent referral for psychiatric evaluation |
Special Considerations for Psychiatric Evaluation
Immediate Psychiatric Evaluation Required
- Any positive response to item 9 (thoughts of self-harm) warrants immediate referral for emergency evaluation by a licensed mental health professional 2
- Presence of psychosis, severe agitation, or confusion also warrants emergency evaluation regardless of total PHQ-9 score 2
Functional Impact Assessment
When determining need for psychiatric evaluation, consider:
- Degree of functional impairment
- Duration of depressive symptoms
- Presence of comorbidities
- Social support and coping skills
Clinical Implementation Tips
Proper Administration
- Administer the complete PHQ-9 (all 9 items)
- Do not omit the self-harm question (item 9) as this may artificially lower the score and miss critical safety concerns 2, 1
- The PHQ-9 has excellent test-retest reliability (coefficient of 0.737) 3
Monitoring and Follow-up
- For patients with scores 8-14 who don't receive immediate referral, schedule follow-up within 2 weeks 1
- Use PHQ-9 to monitor treatment response, with target of 50% reduction in score or achievement of score <5 (remission) 1
Common Pitfalls to Avoid
- Underutilization of validated cutoff scores: Research supports specific thresholds for intervention (15+ for specialist referral) 1
- Omitting the self-harm question: This weakens validity and may miss critical safety concerns 2, 1
- Relying solely on total score: Consider individual item responses, especially item 9 on self-harm
- Inconsistent follow-up: Regular monitoring is essential, especially for moderate scores (8-14) 1
The PHQ-9 has demonstrated good sensitivity (88%) and specificity (88%) for major depression at a cutoff of ≥10 4, but clinical guidelines recommend psychiatric referral at the higher threshold of ≥15 to focus specialized resources on those with moderately severe to severe symptoms 1.