Table 3 Antigenic performance of denatured and soluble recombinant HCV-core and E1/E2 proteins

ROC curve

 Cut-off value

1.03

2.75

 Sensitivity

78.81% (95% CI: 71.62% to 84.57%)

82.11% (95% CI: 76.04% to 86.90%)

 Specificity

78.57% (95% CI: 72.53% to 83.58%)

92.23% (95% CI: 87.57% to 95.23%)

 Likelihood ratio

3.678

10.56

Fischer’s exact test

 Sensitivity

85.42%(95% CI: 0.8039 to 0.8932)

87.64%(95% CI: 0.8322 to 0.9102)

 Specificity

75.24% (95% CI: 0.6892 to 0.8064)

91.23% (95% CI: 0.8603 to 0.9461)

 PPV

80.08% (95% CI: 0.7476 to 0.8451)

94.14% (95% CI: 0.9056 to 0.9642)

 NPV

81.58% (95% CI: 0.7546 to 0.8645)

82.11% (95% CI: 0.7604 to 0.869)

 OR

17.8 (95% CI: 11.07 to 28.65)

73.72 (95% CI: 38.33 to 134.4)

 Relative risk

4.347 (95% CI: 3.24 to 5.941)

5.261 (95% CI:3.921 to 7.198)

 Likelihood ratio

3.45

9.991

 Accuracy

80.72% (95% CI: 76.74% to 84.28%)

89.01% (95% CI: 85.74% to 91.76%)

Lowest detection limit (IU/mL)

19,300

3,800

Concentration of coating Ag/well

250 ng of each Ag

200 ng of each Ag

Lowest reactive serum concentration

1/300

1/1600