Two nanobody-based immunoassays to differentiate antibodies against genotype 1 and 2 porcine reproductive and respiratory syndrome virus

Table 5 Comparisons of the developed g1-2-cELISA and g1-cELISA with commercial IDEXX ELISA kit by detecting challenged and clinical pig serum samples

cELISA	Samples	Positive ( +) or negative (-)	Number	Commercial ELISA kit		Agreement	Kappa value	Positive rate
cELISA	Samples	Positive ( +) or negative (-)	Number	+	-	Agreement	Kappa value	Positive rate
g1-2-cELISA	Challenged sera	+	80	80	0	100%	1.00	65.04%
	Challenged sera	-	43	0	43	100%	1.00	65.04%
	Clinical sera	+	1126	1122	4	99.02%	0.97	73.40%
	Clinical sera	-	408	11	397	99.02%	0.97	73.40%
g1-cELISA	Challenged sera	+	30	30	0	59.35%	0.30	24.39%
	Challenged sera	-	93	50	43	59.35%	0.30	24.39%
	Clinical sera	+	3	2	1	24.84%	0.0004	0.13%
	Clinical sera	-	1531	1122	379	24.84%	0.0004	0.13%