Table 4.

Univariate and multivariate analyses for overall survival of locally advanced (III-IVB) patients using Cox proportional hazards model

	Univariate			Multivariate
	HR	(95% CI)	p value	HR	(95% CI)	p value
Age
<65	1.00		<0.001	1.00		<0.001
≥65	1.64	1.52–1.77		1.30	1.16–1.46
Sex
Male	1.00
Female	1.17	1.07–1.27	<0.001
Race
White	1.00
Non-white	1.35	1.23–1.48	<0.001
Charlson/Deyo comorbidity score
0	1.00			1.00
1	1.33	1.21–1.46	<0.001	1.09	0.96–1.25	0.18
≥2	2.03	1.76–2.34	<0.001	1.81	1.48–2.22	<0.001
Insurance type
Private	1.00			1.00
Non-private/unknown	2.16	1.98–2.34	<0.001	1.38	1.22–1.57	<0.001
Income
<$48,000	1.00
≥$48,000	0.71	0.66–0.77	<0.001
Location
Urban	1.00
Non-urban	1.09	1.00–1.19	<0.05
Facility
Community	1.00
Academic	0.92	0.86–1.00	<0.05
Facility volume
Low	1.00
High	0.82	0.75–0.89	<0.001
Head and neck subsites
Oral cavity	1.00			1.00
Hypopharynx	1.90	1.69–2.13	<0.001	1.37	1.16–1.61	<0.001
Larynx	1.32	1.21–1.45	<0.001	0.93	0.80–1.07	0.28
Dose
None	1.00
Low (50–65 Gy)	0.42	0.37–0.48	<0.001
High (65–80 Gy)	0.38	0.35–0.42	<0.001
Tumor size (cm)	1.30	1.27–1.33	<0.001	1.19	1.15–1.24	<0.001
Primary treatment
No treatment	1.00			1.00
Surgery	0.28	0.24–0.33	<0.001	0.26	0.21–0.33	<0.001
Radiotherapy	0.41	0.34–0.49	<0.001	0.32	0.23–0.44	<0.001
Surgery ≫ radiotherapy	0.19	0.16–0.22	<0.001	0.17	0.14–0.22	<0.001
Chemotherapy	0.67	0.54–0.82	<0.001	0.63	0.47–0.85	<0.01
Chemoradiotherapy	0.16	0.14–0.19	<0.001	0.17	0.14–0.21	<0.001
Surgery ≫ chemoradiotherapy	0.19	0.16–0.22	<0.001	0.18	0.14–0.23	<0.001
T-stage
1	1.00			1.00
2	1.84	1.56–2.18	<0.001	1.33	1.06–1.67	<0.05
3	2.96	2.52–3.48	<0.001	1.59	1.24–2.03	<0.001
4	4.13	3.52–4.85	<0.001	1.96	1.54–2.51	<0.001
N-stage
0	1.00			1.00
1	0.72	0.65–0.81	<0.001	1.37	1.16–1.63	<0.001
2 and 3	0.76	0.69–0.83	<0.001	1.38	1.19–1.61	<0.001
HPV
Negative	1.00			1.00
Positive	0.34	0.31–0.38	<0.001	0.46	0.39–0.53	<0.001