Table V.

Mean CT numbers (HU) of the 9.5 mm-diameter reference nodules for 3 scans at each technique and the standard deviations of the mean CT numbers.

		High Resolution		NLST		LTRC
	Nodule no.	Mean	Standard deviation	Mean	Standard deviation	Mean	Standard deviation
100 mg/cc	1	75.5	0.4	68.6	1.4	85.3	0.4
	2	74.5	1.1	64.3	3.1	86.8	2.2
	3	72.0	0.9	64.0	2.1	82.3	1.5
	4	64.5	1.4	57.5	0.8	75.4	1.7
	5	64.3	0.3	55.4	4.2	78.3	3.0
Overall mean		70.2±5.4		62.0±5.4		81.6±4.8
	6	18.4	0.3	10.5	1.0	33.4	1.9
	7	14.4	0.3	8.5	3.7	28.6	0.9
50 mg/cc	8	13.1	0.1	2.6	0.3	25.9	2.6
	9	14.8	1.9	14.1	1.1	34.3	0.5
	10	23.0	0.3	17.6	2.5	40.7	1.6
Overall Mean		16.7±4.0		10.7±5.7		32.6±5.7