TABLE 3.

Difference in Mean Absolute Volume Error for Each Compression Level Comparison according to Nodule Characteristics

	Nodule Attenuation				Nodule Location				Nodule Diameter
	Ground Glass		Not Ground Glass		Central		Peripheral		>5 mm		≤5 mm
Compression Levels Compared	Estimated Difference (mm3)*	P Value	Estimated Difference (mm3)*	P Value	Estimated Difference (mm3)*	P Value	Estimated Difference (mm3)*	P Value	Estimated Difference (mm3)*	P Value	Estimated Difference (mm3)*	P Value
10:1 vs 20:1	−24.6	.031	−5.1	.011	−35.4	.044	−7.5	.017	−17.9	.034	−7.3	.027
10:1 vs 30:1	−47.0	.002	−9.4	<.001	−62.0	.035	−14.5	<.001	−31.6	.005	−14.1	.003
10:1 vs 40:1	−62.2	<.001	−11.6	<.001	−76.5	.007	−19.3	<.001	−40.0	<.001	−18.9	<.001
20:1 vs 30:1	−22.4	.182	−4.3	.258	−26.6	.492	−7.0	.11	−13.8	.292	−6.8	.282
20:1 vs 40:1	−37.6	.010	−6.5	.016	−41.2	.161	−11.8	<.001	−22.1	.041	−11.6	.012
30:1 vs 40:1	−15.2	.619	−2.2	.648	−14.5	.776	−4.7	.44	−8.4	.790	−4.7	.539

^*The difference between compression levels in terms of the absolute volume error was calculated as the absolute volume error at the lower compression level (eg, 10:1) minus the absolute volume error at the higher compression level (eg, 20:1).