Table 3 Prevalence of reactivity of HBV by chemiluminescence (CLIA) and nucleic acid testing (NAT).
HBsAg (N/%) | Total (N = 87620) | Assuit (N = 75156) | Mansoura (N = 12464) | |||
|---|---|---|---|---|---|---|
CLIA | NAT | CLIA | NAT | CLIA | NAT | |
Non-reactive | 86,944/99.23 | 86,999/99.29 | 74,555/99.2 | 74,603/99.26 | 12,389/99.4 | 12,396/99.46 |
Reactive | 676/0.77 | 621/0.71 | 601/0.8 | 553/0.74 | 75/0.6 | 68/0.54 |
HBsAg + ve NAT + ve (TP) | 589/0.67 | 525/0.7 | 64/0.51 | |||
HBsAg + ve NAT-ve (FP) | 87/0.1 | 76/0.1 | 11/0.09 | |||
HBsAg -ve NAT + ve (FN) (NAT yield) | 32/0.04 | 28/0.04 | 4/0.03 | |||
HBsAg -ve NAT-ve (TN) | 86,912/99.19 | 74,527/99.16 | 12,385/99.37 | |||
Sensitivity, Specificity, PPV, NPV and accuracy of chemiluminescence compared to gold standard test NAT (value, 95% CI) | ||||||
Sensitivity | 94.85% (92.80–96.45%) | 94.94% (92.77–96.61%) | 94.12% (85.62–98.37%) | |||
Specificity | 99.90% (99.88–99.92%) | 99.90% (99.87–99.92%) | 99.91% (99.84–99.96%) | |||
PPV | 87.13% (84.58–89.32%) | 87.35% (84.65–89.64%) | 85.33% (76.27–91.33%) | |||
NPV | 99.96% (99.95–99.97%) | 99.96% (99.95–99.97%) | 99.97% (99.92–99.99%) | |||
Accuracy | 99.86% (99.84–99.89%) | 99.86% (99.83–99.89%) | 99.88% (99.80–99.93%) | |||
Inter-rater agreement - % - Kappa coefficient value | 99.86% 0.907 (very good) | 99.86% 0.909 (very good) | 99.88% 0.895 (very good) | |||
