Table 1.
Comparison of qPCR test results of tissues (intestine and MLN) with reference test (culture and histopathological lesion score) results.
| Sample type | qPCR | Culture |
McNemar’s χ2 (p-value)c | Cohen’s kappa (95% CI)d | Histopathological lesions |
McNemar’s χ2 (p-value)c | Cohen’s kappa (95% CI)d | |||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| +a | −b | Total | +a | −b | Not done | Total | ||||||
| Intestine | + | 53 (88.4%) | 11 (23.5%) | 64 | 0.50 (0.22) | 0.66 (0.52, 0.80) | 42 (85.8%) | 18 (34.0%) | 4 (80.0%) | 64 | 4.00 (0.11) | 0.52 (0.36, 0.68) |
| − | 7 (11.7%) | 36 (76.6%) | 43 | 7 (14.3%) | 35 (66.1%) | 1 (20.0%) | 43 | |||||
| Total | 60 | 47 | 107 | 49 | 53 | 5 | 107 | |||||
| MLN | + | 51 (86.5%) | 19 (39.6%) | 70 | 3.71 (0.13) | 0.48 (0.32, 0.65) | 45 (81.9%) | 19 (41.4%) | 6 (100.0%) | 70 | 2.21 (0.20) | 0.42 (0.24, 0.59) |
| − | 8 (13.6%) | 29 (60.5%) | 37 | 10 (18.2%) | 27 (58.7%) | 0 | 37 | |||||
| Total | 59 | 48 | 107 | 55 | 46 | 6 | 107 | |||||
| Bothe | + | 61 (95.4%) | 19 (44.2%) | 80 | 10.23 (0.01)* | NC | 52 (89.7%) | 23 (52.3%) | 5 (100.0%) | 80 | 8.83 (0.02)* | NC |
| − | 3 (4.7%) | 24 (55.9%) | 27 | 6 (10.4%) | 21 (47.8%) | 0 | 27 | |||||
| Total | 64 | 43 | 107 | 58 | 44 | 5 | 107 | |||||
aPositive test result. Percentage were calculated as proportion of positive test result of reference test.
bNegative test result. Percentage were calculated as proportion of negative test result of reference test.
cMcNemar’s χ2 at three degree of freedom and corresponding p-value.
dCohen’s kappa and 95% CI of the estimate.
eThe parallel test results of both tissues were compared to the parallel test results of reference tests for both tissues.
*McNemar’s χ2 showed ample evidence that the positive proportion of the qPCR of both tissues compared to the reference tests was significantly different.
NC, not calculated; qPCR, quantitative PCR; CI, confidence interval; MLN, mesenteric lymph node.