Table 3.
Mean and 95% posterior credible intervals (PCI) for the sensitivity (Se) and specificity (Sp) of two serum ELISAs and on fecal qPCR and true prevalence (Ps) of MAP in sub-populations 1 to 4
| Mean (95% PCI) | ||||
|---|---|---|---|---|
| Model 1a | Model 2b | Model 3c | ||
| DIC | 120.4 | 134.2 | 227.9 | |
| ELISA A | Se | 17.9 (11.4; 25.6) | 19.7 (13.1; 27.3) | 70.0 (56.0; 85.6) |
| Sp | 94.8 (93.1; 96.3) | 95.0 (93.4; 96.5) | 98.7 (97.4; 99.9) | |
| ELISA B | Se | 17.4 (10.6; 25.9) | 23.2 (15.8; 31.5) | 80.0 (63.7; 95.3) |
| Sp | 94.0 (92.2; 95.7) | 94.8 (93.2; 96.4) | 98.9 (97.5; 99.9) | |
| Fecal qPCR | Se | 47.5 (29.3; 69.9) | 56.3 (36.9; 77.3) | 31.3 (21.8; 41.9) |
| Sp | 99.0 (97.9; 99.7) | 99.4 (98.4; 99.9) | 93.2 (91.6; 94.7) | |
| Sub-pop. 1 | P1 | 0.01 (0.0; 0.03) | 1.2 (0.1; 3.8) | 6.6 (3.1; 11.0) |
| Sub-pop. 2 | P2 | 5.4 (1.6; 11.5) | 6.2 (2.5; 11.9) | 8.1 (4.7; 12.3) |
| Sub-pop. 3 | P3 | 21.7 (13.1; 34.5) | 19.2 (12.1; 29.4) | 8.4 (5.2; 12.3) |
| Sub-pop. 4 | P4 | 57.3 (35.4; 88.8) | 47.2 (31.0; 70.4) | 15.5 (9.7; 22.6) |
| ΔELISA A – ELISA B | Se | 0.5 (−5.6; 5.9) | −3.5 (−9.9; 2.5) | −10.0 (−28.8; 9.3) |
| Sp | 0.8 (−0.8; 2.4) | 0.2 (−1.2; 1.5) | −0.2 (−1.9; 1.5) | |
| ΔFecal PCR – ELISA A | Se | 29.6 (13.7; 50.9) | 36.7 (18.6; 57.9) | −38.8 (−56.4; −22.4) |
| Sp | 4.2 (2.5; 6.0) | 4.4 (2.6; 6.2) | −5.5 (−7.4; −3.7) | |
| Δ Fecal PCR – ELISA B | Se | 30.1 (14.5; 50.8) | 33.1 (16.0; 53.4) | −48.8 (−66.4; −30.8) |
| Sp | 5.0 (3.4; 6.7) | 4.6 (2.8; 6.4) | −5.7 (−7.7; −3.8) | |
Doubtful ELISA and fecal qPCR Ct ≤ 42 results were treated as positive
aModels with pairwise dependence between ELISA A and ELISA B for sensitivity and pairwise dependence between the three tests for specificity
bModels with pairwise dependence between ELISA A and ELISA B for sensitivity and specificity and assuming conditional independence of fecal qPCR
cModels assuming fully conditional independence between the three tests