Table 2 Sensitivity, specificity, positive and negative predictive values, and positive and negative likelihood ratios, and overall accuracy for the diagnostic algorithm and the summary score (≥10) of the PHQ-9
From: Utility and limitations of PHQ-9 in a clinic specializing in psychiatric care
Diagnosis of current major depressive episode (MDE) | Diagnosis of MDE with major depressive disorder | |||
|---|---|---|---|---|
Diagnostic algorithm of PHQ-9 | Summary score (≥10) of the PHQ-9 | Diagnostic algorithm of PHQ-9 | Summary score (≥10) of the PHQ-9 | |
True positive, n (%) | 39 (25) | 47 (31) | 32 (21) | 38 (25) |
False positive, n (%) | 34 (22) | 52 (34) | 41 (27) | 61 (40) |
False negative, n (%) | 11 (7) | 3 (2) | 9 (6) | 3 (2) |
True negative, n (%) | 69 (45) | 51 (33) | 71 (46) | 51 (33) |
Sensitivity (95%CI) | 0.78 (0.64–0.88) | 0.94 (0.84–0.99) | 0.78 (0.62–0.89) | 0.93 (0.80–0.98) |
Specificity (95%CI) | 0.67 (0.57–0.76) | 0.50 (0.40–0.60) | 0.63 (0.54–0.72) | 0.46 (0.36–0.55) |
Positive predictive value (95%CI) | 0.53 (0.41–0.65) | 0.47 (0.37–0.58) | 0.44 (0.32–0.56) | 0.38 (0.29–0.49) |
Negative predictive value (95%CI) | 0.86 (0.77–0.93) | 0.94 (0.85–0.99) | 0.89 (0.80–0.95) | 0.94 (0.85–0.99) |
Positive likelihood ratio (95%CI) | 2.36 (1.76–2.99) | 1.86 (1.56–2.02) | 2.13 (1.59–2.63) | 1.70 (1.41–1.85) |
Negative likelihood ratio (95%CI) | 0.33 (0.19–0.53) | 0.12 (0.04–0.33) | 0.35 (0.19–0.59) | 0.16 (0.05–0.43) |
Overall accuracy (95%CI) | 0.71 (0.64–0.76) | 0.64 (0.58–0.67) | 0.67 (0.61–0.72) | 0.58 (0.53–0.61) |