Development and evaluation of an immunochromatographic strip for rapid detection of porcine hemagglutinating encephalomyelitis virus

Table 3 Agreement between the immunochromatographic strip (ICS) and reference methods

ICS	ELISA^a			RT-PCR^b			Total
ICS	Positive	Negative	Kappa	Positive	Negative	Kappa	Total
Positive	88	0	0.976	88	0	0.976	88
Negative	2	88	0.976	2	88	0.976	90
Total	90	88		90	88		178

^aRelative to ELISA, specificity of ICS: 88/88 × 100% = 100%; sensitivity of ICS: 88/90 × 100% = 97.78%; Po = (88 + 88)/178 = 98.88%;
Pe = [(90/178) × (88/178) + (88/178) × (90/178)] = 0.50; Kappa = (Po-Pe)/(1-Pe) = 0.976.
^bRelative to RT-PCR, specificity of ICS: 88/88 × 100% = 100%; sensitivity of ICS: 88/90 × 100% = 97.78%; Po = (88 + 88)/178 = 98.88%;
Pe = [(90/178) × (88/178) + (88/178) × (90/178)] = 0.50; Kappa = (Po-Pe)/(1-Pe) = 0.976.

ISSN: 1743-422X