Patient-reported outcome measures for technology assessment: A comparison between three-dimensional conformal and intensity-modulated radiotherapy in prostate cancer

Table 3 Linear regression of image-guided radiation therapy characteristics and patient-reported outcomes in intensity-modulated radiotherapy cohort (n = 106), n (%)/mean (SD or SE)

	EPIC urinary incontinence	P value	EPIC urinary irritative/obstructive	P value	EPIC bowel summary	P value	EPIC sexual summary	P value	SF-36 physical component summary	P value	SF-36 mental component summary	P value
Intercept	-22.4 (28.6)	0.436	34.0 (29.4)	0.250	92.2 (36.8)	0.014	45.8 (45.9)	0.320	17.2 (11.5)	0.139	36.8 (12.7)	0.005
Pre-treatment score	0.6 (0.1)	< 0.001	0.4 (0.1)	< 0.001	0.0 (0.2)	0.952	0.5 (0.1)	< 0.001	0.4 (0.1)	< 0.001	0.3 (0.1)	0.001
CBCT+ planning target volume margins combined
No CBCT; > 5 mm	Reference		Reference		Reference		Reference		Reference		Reference
CBCT; 5 mm or less	14.4 (7.2)	0.048	2.6 (7.3)	0.720	-9.9 (6.3)	0.122	0.1 (11.0)	0.989	-3.3 (2.7)	0.217	2.2 (3.3)	0.503
CBCT; > 5 mm	-2.2 (6.0)	0.709	-4.3 (6.2)	0.489	-8.1 (5.3)	0.133	2.2 (9.3)	0.817	-1.7 (2.3)	0.464	-1.1 (2.7)	0.680
Equivalent dose in 2 Gy fractions
≤ 78	Reference		Reference		Reference		Reference		Reference		Reference
> 78	-8.4 (5.2)	0.113	-15.2 (5.4)	0.006	-3.2 (4.7)	0.494	-5.8 (8.0)	0.471	-2.4 (2.1)	0.256	0.0 (2.4)	0.993
Dose per fraction
< 3 Gy/fraction	Reference		Reference		Reference		Reference		Reference		Reference
≥ 3 Gy/fraction	-13.6 (6.2)	0.030	-11.1 (6.1)	0.075	3.5 (5.2)	0.504	-2.4 (9.0)	0.794	4.0 (2.2)	0.070	-3.1 (2.7)	0.253
Risk
Low	Reference		Reference		Reference		Reference		Reference		Reference
Intermediate	-1.2 (5.5)	0.823	3.4 (5.7)	0.550	3.5 (4.9)	0.479	4.4 (8.5)	0.604	3.0 (2.1)	0.148	0.4 (2.5)	0.865
Age	0.8 (0.4)	0.031	0.4 (0.4)	0.334	0.1 (0.3)	0.818	-0.4 (0.6)	0.542	0.1 (0.1)	0.464	0.1 (0.2)	0.752

Equivalent dose in 2 Gy fractions, calculated using the linear-quadratic model to standardize comparisons across different fractionation schedules (α/β prostate: 1.5). CBCT: Cone-beam computed tomography; EPIC: Expanded prostate cancer index composite; SF-36: Short form-36 health survey.