Table 4.

Cox Proportional Hazard Models for Time to Late Grade 3+ Toxicity

		Covariates	HR*	95% C.I. *	p-value†
Late Grade 3+	Age
Total Toxicity
		≤ 70	RL
		> 70	0.78	(0.62, 1.00)	0.0476+
	Treatment
		RT only	RL
		Short-term HR	0.54	(0.39, 0.74)	0.0001+
		Long-term HR	0.77	(0.62, 1.01)	0.0566
Late Grade 3+ GI	Age
Toxicity
		≤ 70	RL
		> 70	0.71	(0.45, 1.11)	0.1289
	Treatment
		RT only	RL
		Short-term HR	0.33	(0.17, 0.62)	0.0006+
		Long-term HR	0.70	(0.43, 1.13)	0.1423
Late Grade 3+	Age
GU Toxicity
		≤ 70	RL
		> 70	0.90	(0.67, 1.20)	0.4636
	Treatment
		RT only	RL
		Short-term HR	0.57	(0.40, 0.84)	0.0037+
		Long-term HR	0.67	(0.48, 0.95)	0.0230+
Late Grade 3+ Other	Age
Toxicity
		≤ 70	RL
		> 70	0.66	(0.33, 1.29)	0.2214
	Treatment
		RT only	RL
		Short-term HR	0.30	(0.11, 0.77)	0.0127+
		Long-term HR	0.74	(0.33, 1.29)	0.4109

^*HR=Hazard ratio, RL=Reference level, C.I. is the confidence interval.

^†p-value is from Chi-square test using the Cox proportional hazards model.