Table 3.

Specificity and sensitivity of the ELISAs using recombinant NcSUB1 fragments compared with the ELISA results with the reference antigen, NcSAG1t^a

Antigen	Sensitivity, % (95% CI)	Specificity, % (95% CI)	Kappa value (95% CI)
NcSUB1t	94.59 (86.02–98.25)	80.00 (29.88–98.95)	0.58 (0.23–0.94)
NcSUB1tr	95.95 (87.82–98.95)	100 (46.29–100)	0.75 (0.47–1)
N54	98.36 (90.02–99.90)	38.89 (18.26–63.86)	0.46 (0.18–0.74)

^aShown are the specificity and sensitivity of the ELISAs using recombinant NcSUB1 fragments for detection of the IgG antibodies to infection in field bovine sera compared with the ELISA results with the reference antigen, NcSAG1t (n = 79). Kappa values with 95% confidence intervals (CI) were computed using http:/vassarstats.net/. The strength of agreement between antigens was graded with kappa values of fair (0.21 to 0.40), moderate (0.41 to 0.60), and substantial (0.61 to 0.80).