The Korean Journal of Clinical Laboratory Science : eISSN 2288-1662 / pISSN 1738-3544

Table 3.

The NAb concentrations of the tested 37 positive samples from NIBSC

Result Control
Positive Negative Sum
Study Positive 22 (a) 2 (b) 24 (a+b)
Negative 0 (c) 100 (PM) (d) 113 (c+d)
13 (<3.8, NIBSC) (d)
Sum 22 (a+c) 115 (b+d) 137 (a+b+c+d)

The evaluation of relative clinical sensitivity (positive percent agreement; PPA) and specificity (negative percent agreement; NPA) of the recombinant RBD antigen applied LFA kits compared to a previously marketed NAb detection kit (confidence interval; CI=95%).

Agreement is assessed in terms of Cohen’s kappa; Kappa statistic must be at or in excess of 80%.

∙PPA (%)=100×a/(a+c): 100%. ∙NPA (%)=100×d/(b+d): 98.3%. ∙Overall rate of Agreement (%)=100×(a+d)/(a+b+c+d): 98.5%.

Korean J Clin Lab Sci 2021;53:257-65
© 2021 Korean J Clin Lab Sci