Table 4. Assay results of RDTs and PCR (PCR as gold standard).
| Assay | PCR | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Positive | Negative | Sens. | Spec. | PPV | NPV | Accuracy | CUI+* | CUI- | p-value# | ||
| SD Cholera Kit | Positive | 115 | 11 | 52.3% | 96.1% | 91.3% | 72.4% | 77.1% | 0.477 | 0.695 | 0.5002 |
| Negative | 105 | 275 | (45.4–59) | (93.2–98.1) | (84.9–95.6) | (67.6–76.8) | (73.2–80.7) | ||||
| SMART—II Kit | Positive | 128 | 22 | 58.2% | 92.3% | 85.5% | 74.2% | 77.5% | 0.497 | 0.684 | 0.0152 |
| Negative | 92 | 264 | (51.4–64.8) | (88.6–95.1) | (78.6–90.6) | (69.3–78.6) | (73.6–81) | ||||
| Crystal VC Kit | Positive | 122 | 9 | 55.4% | 96.8% | 93.1% | 73.8% | 78.8% | 0.515 | 0.714 | 0.0604 |
| Negative | 98 | 277 | (48.6–62.1) | (94.1–98.5) | (87.4–96.8) | (69.1–78.2) | (75–82.3) | ||||
*CUI; Clinical utility index of the positive and negative test. >0.81 excellent utility; 0.64–0.80 good utility; 0.49–0.63 fair utility; 0.36–0.48; poor utility and <0.36 very poor utility [34].
#Fisher’s exact test.