Table 2.

Diagnostic assessment of the three automated analyzers for SARS-CoV-2 IgG detection using RT-PCR as a reference test for the (A) overall sample, (B) symptomatic patient group, and (C) asymptomatic patient group.

		RT-PCR			Overall Percent Agreement	Sensitivity	Specificity	Cohen’s Kappa Statistic
		Positive	Negative	Total	% (95% CI)	% (95% CI)	% (95% CI)	k (95% CI)
(A)
	Negative	11	121	132
	Total	111	127	238
VIDAS®3 assay	Positive	98	2	100	93.7 (89.9–96.2)	88.3 (81.0–93.0)	98.4 (94.5–99.6)	0.87 (0.83–0.92)
	Negative	13	125	138
	Total	111	127	238
CL-900i® assay	Positive	100	6	106	92.9 (88.9–95.5)	90.1 (83.1–94.4)	95.3 (90.1–97.8)	0.86 (0.81–0.90)
	Negative	11	121	132
	Total	111	127	238
LIAISON®XL assay	Positive	95	0	95	93.3 (89.4–95.8)	85.6 (77.9–90.9)	100 (97.1–100)	0.86 (0.82–0.91)
	Negative	16	127	143
	Total	111	127	238
(B)
VIDAS®3 assay	Positive	54	2	56	97.8 (94.5–99.1)	96.4 (87.9–99.0)	98.4 (94.5–99.6)	0.95 (0.92–0.98)
	Negative	2	125	127
	Total	56	127	183
CL-900i® assay	Positive	55	6	61	96.2 (92.3–98.1)	98.2 (90.6–99.7)	95.3 (90.1–97.8)	0.91 (0.87–0.95)
	Negative	1	121	122
	Total	56	127	183
LIAISON®XL assay	Positive	51	0	51	97.3 (93.8–98.8)	91.1 (80.7–96.1)	100 (97.1–100)	0.93 (0.90–0.97)
	Negative	5	127	132
	Total	56	127	183
(C)
	Negative	10	121	131
	Total	51	127	178
VIDAS®3 assay	Positive	40	2	42	92.7 (89.8–96.2)	78.4 (64.7–88.7)	98.4 (94.5–99.6)	0.81 (0.75–0.87)
	Negative	11	125	136
	Total	56	127	178
CL-900i® assay	Positive	41	6	47	91.0 (85.9–94.4)	80.4 (67.5–89.0)	95.3 (90.1–97.8)	0.77 (0.71–0.84)
	Negative	10	121	131
	Total	51	127	178
LIAISON®XL assay	Positive	40	0	40	93.8 (89.3–96.5)	78.4 (65.4–87.5)	100 (97.1–100)	0.84 (0.78–0.90)
	Negative	11	121	131
	Total	51	127	178