Table 3.
Specificity values obtained in the 3rd group of animals, adopting the 2nd, 3rd, and 5th interpretative criteria of the IFN-γ test.
| Interpretative criteria | N | TN | FP | %FP | SP | CI 95% SP | ||
|---|---|---|---|---|---|---|---|---|
| 2 | A-PBS > 0.1 = MAP | 80 | 73 | 7 | 8.75% | 91.25% | 82.80% | 96.41% |
| Ja-PBS > 0.1 = MAP | 80 | 76 | 4 | 5.00% | 95.00% | 87.69% | 98.62% | |
| Jb-PBS > 0.1 = MAP | 80 | 70 | 10 | 12.50% | 87.50% | 78.21% | 93.84% | |
| 3 | A-PBS > 0.2 = MAP | 80 | 79 | 1 | 1.25% | 98.75% | 93.23% | 99.97% |
| Ja-PBS > 0.2 = MAP | 80 | 80 | 0 | 0.00% | 100.00% | 95.49% | 100.00% | |
| Jb-PBS > 0.2 = MAP | 80 | 76 | 4 | 5.00% | 95.00% | 87.69% | 98.62% | |
| 5 | A-(2 * PBS) > 0.04 = MAP | 80 | 74 | 6 | 7.50% | 92.50% | 84.39% | 97.20% |
| Ja-(2 * PBS) > 0.04 = MAP | 80 | 77 | 3 | 3.75% | 96.25% | 89.43% | 99.22% | |
| Jb-(2 * PBS) > 0.04 = MAP | 80 | 73 | 7 | 8.75% | 91.25% | 82.80% | 96.41% | |
Specificity for IFN-y test criteria estimated on a sample of 80 animals from a Mycobacterium avium subsp. paratuberculosis (MAP) free herd with an ongoing bovine tuberculosis outbreak.
N, number of assessed animals; TN, true negative; FP, false positive; SP CI 95%, specificity and confidence interval 95%; A, avian PPD; Ja, Johnin PPD from strain A; Jb, Johnin PPD from strain B; PBS, phosphate-buffered saline.