Table 1.
Sensitivity, specificity, PPV, and NPV of typhoid fever diagnostic tests, using blood culture and a composite reference standard (blood culture and real-time PCR) as comparators
| Test | % (95% confidence interval) |
|||
|---|---|---|---|---|
| Sensitivity | Specificity | PPV | NPV | |
| Blood culture | ||||
| Tubex | 77.3 (59.8–94.8) | 87.4 (84.5–90.4) | 0.221 (0.128–0.313) | 0.988 (0.978–0.998) |
| TyphiDot | 95.5 (86.8–104) | 79.1 (75.4–82.7) | 0.174 (0.106–0.241) | 0.997 (0.992–1.00) |
| TR-02 | 100 | 81.6 (85.1–78.1) | 0.200 (0.125–0.275) | 1 |
| Widal (titer, 160) | 86.4 (72.0–100.7) | 95.0 (93.0–96.9) | 0.442 (0.293–0.590) | 0.993 (0.986–1.001) |
| Blood culture plus PCR (composite reference standard) | ||||
| Tubex | 51.1 (36.8–65.4) | 88.3 (85.3–91.2) | 0.312 (0.208–0.415) | 0.946 (0.924–0.967) |
| TyphiDot | 70.0 (52.4–79.5) | 80.1 (76.5–83.8) | 0.256 (0.178–0.334) | 0.958 (0.938–0.978) |
| TR-02 | 89.4 (80.5–98.2) | 85.0 (81.7–88.3) | 0.382 (0.291–0.473) | 0.987 (0.976–0.998) |
| Widal (titer, 160) | 51.1 (36.8–65.4) | 95.8 (94.0–97.7) | 0.558 (0.410–0.707) | 0.950 (0.930–0.970) |