Table 2.

Hazard ratios for overall survival^*

Variable	Values	Coef	SE	HR	95% CI	P
Sex	Male			ref		.011
	Female	–0.28	0.11	0.76	0.61–0.94
Age (y)	≤70			ref
		0.024	0.015	1.02	0.99–1.05	.1402
WHO-PS	0			ref		.0008
	1	0.31	0.11	1.37	1.11–1.68
	≥2	0.52	0.16	1.68	1.22–2.31
PLNS	0			ref		<.0001
	1	0.27	0.16	1.31	0.95–1.80
	2	0.49	0.16	1.63	1.19–2.24
	3	0.67	0.18	1.96	1.38–2.79
	≥4	0.79	0.18	2.21	1.55–3.14
T stage	T0/T1			ref		.3135
	T2	0.10	0,16	1,11	0.81–1.52
	T3	0.32	0,21	1.8	0.92–2.07
	T4	0.06	0.17	1.06	0.76–1.50
LN GTV (mL)		0.15	0.01	1.16	1.14–1.18	.0008
OTT (days)	≤28			ref
		0.040	0.009	1.04	1.02–1.06	<.0001
EQD2		–0.015	0.008	0.99	0.97–1.00	.0506

Abbreviations: CI = confidence interval; Coef = regression coefficient; EQD₂ = equivalent radiation dose at 2 Gy; GTV = gross tumor volume; LN = natural logarithm; OTT = overall treatment time radiation therapy; PLNS = number of positive lymph node stations; SE = standard error; WHO-PS = World Health Organization performance status.

^*Model is stratified by treatment.