Table 6.

Single region vs multiple subregion analysis for 2× and 4× base technique dose: Overall RMS errors of the bone (vf), fat (vf), and red marrow (vf) of the six test inserts. Internal calibration.

		Bone RMS error (vf)			Fat RMS error (vf)			Red marrow RMS error (vf)
Partition	Region/subregion size (mm)	S	M	L	S	M	L	S	M	L
2× dose
1 × 1	17 × 17	0.0047	0.0034	0.0074	0.031	0.023	0.050	0.036	0.026	0.057
2 × 2	9 × 9	0.0063	0.0078	0.0112	0.041	0.050	0.071	0.047	0.057	0.081
3 × 3	6 × 6	0.0102	0.0110	0.0169	0.069	0.071	0.107	0.079	0.082	0.124
4× dose
1 × 1	17 × 17	0.0049	0.0041	0.0041	0.032	0.030	0.032	0.037	0.033	0.036
2 × 2	9 × 9	0.0060	0.0066	0.0069	0.039	0.043	0.047	0.045	0.049	0.053
3 × 3	6 × 6	0.0076	0.0084	0.0106	0.050	0.056	0.070	0.058	0.064	0.080

¹S = small phantom; M = medium phantom; L = large phantom.