TABLE 2.
Performance of FDA-cleared Chagas disease IgG serological assays compared to original blood donor status, consensus among current tests, and latent class analysis
| Assaya | Value(s) |
||||
|---|---|---|---|---|---|
| Blood donor status |
Consensus status |
Latent class analysis | |||
| Positive | Negative | Positive | Negative | ||
| Hemagen ELISA | |||||
| No. of positive specimens | 440b | 0 | 439b | 1 | |
| No. of negative specimens | 60 | 300 | 45 | 315 | |
| Sensitivity (%) (95% CI) | 88.00 (84.82, 90.72) | 90.70 (87.76, 93.14) | 92.04 (88.93, 95.04) | ||
| Specificity (%) (95% CI) | 100.00 (98.88, 100.00) | 99.68 (98.25, 99.99) | 99.04 (97.20, 100.00) | ||
| PPV (%) (95% CI) | 100.00 (99.17, 100.00) | 99.77 (98.74, 99.99) | |||
| NPV (%) (95% CI) | 83.33 (79.07, 87.03) | 87.50 (83.63, 90.73) | |||
| Ortho ELISA | |||||
| No. of positive specimens | 462 | 0 | 461 | 1 | |
| No. of negative specimens | 38 | 300 | 23 | 315 | |
| Sensitivity (%) (95% CI) | 92.40 (89.72, 94.57) | 95.25 (92.95, 96.96) | 96.50 (94.20, 99.29) | ||
| Specificity (%) (95% CI) | 100.00 (98.78, 100.00) | 99.68 (98.25, 99.99) | 98.82 (96.25, 100.00) | ||
| PPV (%) (95% CI) | 100.00 (99.20, 100.00) | 99.78 (98.80, 99.99) | |||
| NPV (%) (95% CI) | 88.76 (84.90, 91.92) | 93.20 (89.96, 95.64) | |||
| Wiener ELISA | |||||
| No. of positive specimens | 470c | 2d | 466e | 6f | |
| No. of negative specimens | 30 | 298 | 18 | 310 | |
| Sensitivity (%) (95% CI) | 94.00 (91.55, 95.92) | 96.28 (94.19, 97.78) | 97.12 (94.81, 99.24) | ||
| Specificity (%) (95% CI) | 99.33 (97.61, 99.92) | 98.10 (95.91, 99.30) | 96.67 (93.92, 98.96) | ||
| PPV (%) (95% CI) | 99.58 (98.48, 99.95) | 98.73 (97.25, 99.53) | |||
| NPV (%) (95% CI) | 90.85 (87.20, 93.74) | 94.51 (91.47, 96.72) | |||
| InBios CDP | |||||
| No. of positive specimens | 487 | 23 | 480 | 30 | |
| No. of negative specimens | 13 | 277 | 4 | 286 | |
| Sensitivity (%) (95% CI) | 97.40 (95.59, 98.61) | 99.17 (97.90, 99.77) | 99.29 (98.34, 100.00) | ||
| Specificity (%) (95% CI) | 92.33 (88.82, 95.08) | 90.51 (86.72, 93.50) | 87.53 (82.24, 91.94) | ||
| PPV (%) (95% CI) | 95.49 (93.31, 97.12) | 94.12 (91.71, 96.00) | |||
| NPV (%) (95% CI) | 95.52 (92.46, 97.59) | 98.62 (96.51, 99.62) | |||
a
NPV, negative predictive value; PPV, positive predictive value.
b
Data include 11 specimens with indeterminate results. Indeterminate results were classified as positive results for the purpose of these analyses (see text for explanation).
c
Data include 4 specimens with indeterminate results.
d
These 2 specimens had indeterminate results.
e
Data include 3 specimens with indeterminate results.
f
Data include 3 specimens with indeterminate results.