Table 3. Assay results of RDTs and enrichment culture (Culture technique as gold standard).
| Assay | Enriched Culture | Sens. | Spec. | PPV | NPV | Accuracy | CUI+* | CUI-* | p-value# | ||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Positive | Negative | ||||||||||
| SD Cholera | Positive | 111 | 3 | 71.2% (63.4–78.1) |
99.1% (97.5–99.8) |
97.4% (92.5–99.5) |
88.5% (84.9–91.5) |
90.5% (87.6–92.9) |
0.693 |
0.877 |
<0.0001 |
| Negative | 45 | 347 | |||||||||
| SMART-II | Positive | 123 | 19 | 78.8% (71.6–85) |
94.6% (91.7–96.7) |
86.6% (79.9–91.7) |
90.9% (87.5–93.7) |
89.7% (86.7–92.2) |
0.682 |
0.854 |
<0.0001 |
| Negative | 33 | 331 | |||||||||
| Crystal VC | Positive | 122 | 6 | 78.2% (70.9–84.4) |
98.3% (96.3–99.4) |
95.3% (90.1–98.3) |
91.0% (87.6–93.7) |
92.1% (89.4–94.3) |
0.745 |
0.894 |
<0.0001 |
| Negative | 34 | 344 | |||||||||
Number in the parentheses indicate the range
*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.