Table 3.
The diagnostic accuracies of eight brands of VCA-IgA kits and the EBNA1-IgA kit in distinguishing between NPC cases and controls
| Kits | Cut-off values† | Sensitivity (%) | Specificity (%) | AUC (95% CI) | p Value§ | ||
| Early stage (95% CI) | Advanced stage (95% CI)‡ | Total (95% CI) | Control (95% CI) | ||||
| VCA-IgA | |||||||
| BB | 0.58 | 75.8 (58.0 to 89.0) | 88.6 (84.2 to 93.0) | 86.5 (81.8 to 91.2) | 92.0 (88.2 to 95.8) | 0.940 (0.916 to 0.964) | 0.002 |
| BNV | 0.923 | 72.7 (54.0 to 87.0) | 88.0 (83.5 to 92.5)* | 86.0 (81.2 to 90.8) | 93.5 (90.1 to 96.9) | 0.936 (0.911 to 0.961) | 0.003 |
| GBI | 0.825 | 72.7 (54.0 to 87.0) | 76.6 (70.8 to 82.5) | 76.0 (70.1 to 81.9) | 92.0 (88.2 to 95.8) | 0.899 (0.868 to 0.930) | 0.341* |
| HA | 0.884 | 93.9 (80.0 to 99.0) | 88.0 (83.5 to 92.5) | 89.0 (84.7 to 93.3) | 86.0 (81.2 to 90.8) | 0.926 (0.900 to 0.953) | 0.012 |
| HK | 1.218 | 81.8 (64.0 to 93.0) | 83.2 (78.1 to 88.4) | 83.0 (77.8 to 88.2) | 89.5 (85.3 to 93.7) | 0.913 (0.884 to 0.942) | 0.075* |
| KSB | 0.283 | 100.0 (89.0 to 100.0) | 86.8 (82.1 to 91.5) | 89.0 (84.7 to 93.3) | 87.5 (82.9 to 92.1) | 0.945 (0.925 to 0.966) | 0.000 |
| ZS | 0.418 | 75.8 (58.0 to 89.0) | 74.3 (68.2 to 80.3) | 74.5 (68.5 to 80.5) | 87.5 (82.9 to 92.1) | 0.868 (0.831 to 0.904) | 0.878* |
| EUROIMMUN | 1.561 | 87.9 (72.0 to 97.0) | 85.6 (80.8 to 90.5) | 86.0 (81.2 to 90.8) | 90.0 (85.8 to 94.2) | 0.942 (0.921 to 0.964) | |
| EBNA1-IgA | 1.203 | 93.9 (80.0 to 99.0) | 86.2 (81.5 to 91.0) | 87.5 (82.9 to 92.1) | 92.5 (88.8 to 96.2) | 0.956 (0.937 to 0.975) | 0.000 |
†Cut-off value for NPC diagnosis was defined as the value with the largest Youden Index chosen from each ROC.
‡Differences in the sensitivities of early-stage and advanced-stage NPC were compared by Pearson’s χ2 tests. *p<0.05 was considered as statistically significant.
§p Values were estimated by non-inferiority tests based on the bootstrap approach for AUC between EUROIMMUN and other kits. *p<0.05 was considered as statistically significant, whereas p>0.05 was consider to be inferior to the standard kit.
AUC, areas under the curve; EBNA, Epstein-Barr virus nuclear antigen; NPC, nasopharyngeal carcinoma; ROC, receiver operating characteristic; VCA, viral capsid antigen.