Table 1. Specificities, Sensitivities, PPV, and NPV for SARS-CoV-2 Specific IgM and IgG Antibody With ELISA^a.

	cut-off	group A sera	group B sera	specificity (%)	sensitivity (%)	PPV (%)	NPV (%)
IgM	0.233	160/168	90/90	100	95.24	100	91.84
IgG	0.290	163/168	90/90	100	97.02	100	94.74
IgM and IgG	NA	168/168	90/90	100	100	100	100

^aIgM and IgG indicated that a sample was either IgM- or IgG-positive or positive to both IgM and IgG.