TABLE 1.

Comparison of RIPA, IHA, and ELISA reactivity results with positive (titer of ≥1:20) IFA results^a

IFA titer	n	No. of reactive specimens with assay
		RIPA	IHA		ELISA
			Hemagen	Biolab	Abbott	Embrabio	Organon	Gull
1:20	9	1	0	0	0	0	4	3
1:40	35	32	34	24	32	32	35	35
1:80	56	56	56	50	56	56	56	56
1:160	101	101	101	99	99	100	101	101
Total no. positive	201	190	191	173	187	188	196	195
% Agreement	NAb	95	95	86	93	94	98	97

^aData are grouped by the number of reactive specimens identified by each test at various IFA-positive (values of ≥1:20) titers. The percentage of agreement was defined as the total number of positive specimens for each test divided by 201 (total number IFA positive) and multiplied by 100. 

^bNA, not applicable.