Table 3.
Characteristics of screening and diagnostic tests in comparison to BDI-II (gold standard)
| PHQ-2 ≥ 1 (screening test) | PHQ-2 = 2 | PHQ-2: Q1 (depressive mood) | PHQ-2: Q2 (anhedonia) | BDI-FS-Fr and BDI-II (diagnostic test) | |
|---|---|---|---|---|---|
| Sensitivity, % | 64 | 79 | 63 | 79 | 83 |
| CI: 50–77 | CI: 57–91 | CI: 47–76 | CI: 60–91 | IC: 66–93 | |
| Specificity, % | 92 | 79 | 87 | 82 | 89 |
| CI: 83–97 | CI: 69–86 | CI: 77–93 | CI: 73–89 | IC:80–94 | |
| Likelihood ratios positive | 8.25 | 3.74 | 4.79 | 4.49 | 7.31 |
| CI: 3.46–19.67 | CI: 2.36–5.94 | CI: 2.49–9.22 | CI: 2.71–7.42 | IC: 3.88–13.81 | |
| Likelihood ratios negative | 0.39 | 0.27 | 0.43 | 0.25 | 0.19 |
| CI: 0.26–0.58 | CI: 0.11–0.64 | CI: 0.29–0.65 | CI: 0.12–0.56 | IC: 0.08–0.42 | |
| Diagnostics odds ratio | 21.39 | 14.01 | 11.11 | 17.73 | 38.89 |
| CI: 7.13–64.13 | CI: 4.164–47.16 | CI: 4.30–28.70 | CI: 5.72–5.01 | IC:11.89–127.16 | |
| Positive predictive value, % | 85.29 | 44.12 | 73.53 | 55.88 | 73.53 |
| CI: 69.87–93.55 | CI: 28.88–60.55 | CI: 56.88–85.40 | CI: 39.45–71.12 | IC: 56.88–85.40 | |
| Negative predictive value, % | 78.67 | 94.67 | 80.00 | 93.33 | 93.33 |
| CI: 68.12–86.42 | CI: 87.07–97.91 | CI: 69.58–87.49 | CI: 85.32–97.12 | IC: 85.3–97.12 | |
| Prevalence, % | 41.28 | 17.43 | 36.70 | 22.02 | 27.52 |
| Accuracy, % | 80.73 | 78.90 | 78.00 | 81.65 | 0.87 |
| Accuracy +, % | 73 | 57 | 68 | 66 | 0.78 |
| Accuracy −, % | 85 | 86 | 83 | 88 | 0.91 |
| Youden ' s index | 0.57 | 0.58 | 0.49 | 0.62 | 0.72 |
| Yule ' s Q coefficient | 0.91 | 0.87 | 0.83 | 0.89 | 0.95 |
| χ2 | 39.48 | 24.45 | 28.86 | 33.00 | 52.43 |
CI, confidence interval (95%).