Table 5.

Readers diagnostic performance by using CO-RADS to detect COVID-19 in CT chest when CO-RADS category of 3 or more is considered as threshold positive

Groups	Reader No.	AUC vs RT-PCR	Fleiss’ K within groups for CO-RADS ≥ 3	AUC within groups for CO-RADS ≥ 3	Sensitivity within groups for CO-RADS ≥ 3	Specificity within groups for CO-RADS ≥ 3
Chest radiologists	R1	0.90 (0.85, 0.95)	0.88 (0.80, 0.95)	0.91 (0.88, 0.94)	0.90 (0.85, 0.94)	0.82 (0.75, 0.88)
	R2	0.92 (0.87, 0.96)
General radiologists	R3	0.97 (0.95, 0.99)	0.83 (0.75, 0.92)	0.96 (0.94, 0.98)	0.91 (0.87, 0.95)	0.97 (0.93, 0.99)
	R4	0.95 (0.92, 0.98)
Radiologists in training	R5	0.89 (0.83, 0.94)	0.84 (0.76, 0.92)	0.90 (0.87, 0.90)	0.91 (0.86, 0.95)	0.83 (0.76, 0.89)
	R6	0.93 (0.89, 0.97)
Overall		0.92 (0.91, 0.94)	0.84 (0.76, 0.92)	0.92 (0.91, 0.94)	0.90 (0.88, 0.93)	0.87 (0.83, 0.91)

Note: The area under the curve for each observer is compared to reference standard defined by reverse transcriptase polymerase chain reaction (RT-PCR) positivity. The inter-observer agreement, area under the curve, sensitivity, specificity, and diagnostic accuracy within the various groups when threshold for COVID-19 positivity is defined by CO-RADS ≥ 3. Data in parenthesis are 95% confidence intervals