Pooled estimates of the sensitivity, specificity, positive and negative likelihood ratios and diagnostic odds ratios of the brief Patient Health Questionnaire (PHQ-9) for diagnosing major depressive disorder, by cut-off score
| Cut-off score | No. of studies | No. of patients | Sensitivity (95% CI) | Specificity (95% CI) | Positive likelihood ratio (95% CI) | Negative likelihood ratio (95% CI) | Diagnostic odds ratio (95% CI) |
|---|---|---|---|---|---|---|---|
| 7 | 5 | 2794 | 0.83 (0.70–0.91) | 0.73 (0.63–0.82) | 3.20 (2.21–4.63) | 0.22 (0.12–0.41) | 14.18 (6.21–32. 33) |
| 8 | 6 | 3306 | 0.82 (0.66–0.92) | 0.83 (0.69–0.92) | 5.17 (2.30–11.58) | 0.20 (0.08–0.47) | 25.46 (5.34–121.38) |
| 9 | 7 | 3269 | 0.83 (0.68–0.92) | 0.86 (0.76–0.92) | 6.07 (3.35–11.01) | 0.18 (0.08–0.39) | 32.23 (10.06–103. 25) |
| 10 | 16 | 5782 | 0.85 (0.75–0.91) | 0.89 (0.83–0.92) | 7.83 (5.22–11.74) | 0.16 (0.09–0.27) | 47.50 (22.94–98.35) |
| 11 | 10 | 3451 | 0.89 (0.75–0.96) | 0.89 (0.79–0.94) | 8.43 (4.29–16.58) | 0.11 (0.04–0.29) | 75.03 (25.29–222.53) |
| 12 | 10 | 3451 | 0.77 (0.60–0.88) | 0.91 (0.84–0.95) | 8.86 (5.65–13.90) | 0.24 (0.13 – 0.44) | 36.15 (20.16–64.85) |
| 13 | 8 | 2759 | 0.81 (0.75–0.85) | 0.92 (0.86–0.95) | 10.19 (6.19 – 16.77) | 0.20 (0.15–0.26) | 50.03 (29.81–83.97) |
| 14 | 6 | 2162 | 0.67 (0.57–0.76) | 0.95 (0.90–0.97) | 14.23 (7.10 – 28.52) | 0.33 (0.24–0.45) | 42.13 ( 18.73–94.74) |
| 15 | 6 | 2482 | 0.62 (0.48–0.74) | 0.96 (0.94–0.97) | 18.57 (11.37–30.33) | 0.39 (0.27–0.55) | 47.60 (23.09–98.14) |
Note: CI = confidence interval.