Table 1.
Number of samples called positive by each test and overall sensitivity and specificity
| Reference classificationa | Total no. of samples | No. (%b) of samples testing positive with each test or % sensitivity/specificity (95% CI) |
||
|---|---|---|---|---|
| Toxigenic culture | illumigene C. difficile | Xpert C. difficile/Epi | ||
| Toxin positive/C. difficile positive | 64 | 62 (96.9) | 63 (98.4) | 64 (100.0) |
| Toxin negative/C. difficile positive | 36 | 32 (88.9) | 21 (58.3) | 36 (100.0) |
| C. difficile negative | 468 | 0 (0.0) | 0 (0.0) | 6 (1.3) |
| Sensitivity | 100 | 94 (89.4–98.7) | 84 (76.8–91.2) | 100 (95.4–100) |
| Specificity | 468 | 100 (99.0–100) | 100 (99.0–100) | 98.7 (97.7–99.7) |
a
≥2 tests positive.
b
Percentages are the number of samples positive by the test/the number of samples positive by the reference classification times 100.