Table 1.

Comparison of 4DCT, average CBCT, and 4DCBCT ITV contours using the following evaluation metrics: Hausdorff distance, center of mass difference, and dice coefficient.

Patient	4DCT ‐ Average CBCT (1)						4DCT ‐ 4DCBCT (2)						Average CBCT ‐ 4DCBCT (3)
	Hausdorff distance (mm)		COM (mm)		dice coefficient		Hausdorff distance (mm)		COM (mm)		dice coefficient		Hausdorff distance (mm)		COM (mm)		dice coefficient
	mean	SD	mean	SD	mean	SD	mean	SD	mean	SD	mean	SD	mean	SD	mean	SD	mean	SD
1	3.5	0.4	1.3	0.3	0.8	0.0	5.0	0.9	1.5	0.7	0.8	0.0	4.9	0.7	1.2	0.3	0.9	0.1
2	5.1	0.5	0.9	0.4	0.8	0.0	6.0	0.7	1.8	0.6	0.9	0.0	7.2	0.5	1.5	0.6	0.8	0.0
3	5.3	0.5	1.5	0.7	0.8	0.0	6.8	0.5	1.7	0.8	0.8	0.0	7.0	0.6	1.5	0.4	0.8	0.0
4	3.8	0.8	1.2	0.6	0.8	0.0	7.0	1.0	2.4	0.4	0.6	0.1	7.3	1.1	1.9	0.9	0.6	0.1
5	3.7	0.8	1.8	0.5	0.8	0.1	4.3	0.3	1.9	0.5	0.8	0.0	3.9	1.0	0.7	0.3	0.9	0.1
6	8.6	0.9	2.5	1.6	0.6	0.1	11.6	1.2	3.2	0.4	0.4	0.1	7.7	0.8	2.3	0.8	0.8	0.1
7	9.9	1.2	2.3	0.6	0.6	0.0	11.8	1.1	6.2	1.1	0.7	0.0	13.3	1.3	7.0	1.1	0.5	0.1
8	9.2	1.1	4.3	3.0	0.6	0.0	9.0	1.7	5.0	2.7	0.7	0.0	7.2	2.0	1.4	0.6	0.7	0.1
9	9.1	0.7	4.5	1.5	0.8	0.0	12.5	1.3	4.2	2.2	0.6	0.1	14.1	2.8	6.1	0.8	0.6	0.1
Mean Group Error (M)	6.5		2.3		0.7		8.2		3.1		0.7		8.1		2.6		0.7
Systematic Error (Σ)	2.5		1.2		0.1		2.9		1.6		0.1		3.2		2.1		0.1
Random Error (σ)	0.8		1.3		0.0		1.0		1.3		0.0		1.4		0.7		0.1