Table 3.

Multivariate analyses of survival among patients with oral squamous cell carcinoma.

Characteristic	CD-I cohort (N = 118)		CD-II cohort 2 (N = 156)		CD cohort combined (N = 274)		GZ cohort (N = 94)
OS at five years		OS at five years		OS at five years		OS at five years
HR	P Value⁎	HR	P Value⁎	HR	P Value⁎	HR	P Value⁎
(95% CI)		(95% CI)		(95% CI)		(95% CI)
Smoking history
Never	Reference	0.072	Reference	0.979	Reference	0.180	Reference	0.349
Ever	1.87 (0.65–3.68)		1.01 (0.59–1.72)		1.32 (0.88–1.98)		1.45 (0.67–3.13)
Drinking history
Never	Reference	0.717	Reference	0.023	Reference	0.065	Reference	0.103
Ever	1.14 (0.57–2.28)		1.86 (1.09–3.16)		1.47 (0.98–2.22)		1.89 (0.88–4.07)
Cell differentiation
High	Reference	0.036	Reference	0.078	Reference	0.006	Reference	0.014
Moderate or Low	1.98 (1.05–3.75)		1.55 (0.95–2.50)		1.70 (1.16–2.48)		2.84 (1.23–6.52)
Tumor stage
T1 or T2	Reference	0.040	Reference	0.399	Reference	0.011	Reference	0.991
T3 or T4	2.20 (1.04–4.69)		1.23 (0.76–1.97)		1.65 (1.12–2.44)		1.01 (0.46–2.19)
Nodal stage
N0	Reference	0.316	Reference	0.012	Reference	0.016	Reference	0.016
N1-N3	1.40 (0.72–2.72)		1.89 (1.15–3.10)		1.62 (1.09–2.40)		2.61 (1.20–5.69)
Radiotherapy or chemotherapy
Yes	Reference	0.004	Reference	0.141	Reference	0.001	Reference	0.051
No	2.47 (1.34–4.53)		1.44 (0.89–2.35)		1.82 (1.26–2.61)		2.17 (1.00–4.69)
PA28γ
Low expression	Reference	< 0.001	Reference	< 0.001	Reference	< 0.001	Reference	< 0.001
High expression	5.14 (2.51–10.5)		2.82 (1.73–4.61)		3.02 (1.05–4.43)		6.39 (2.12–19.3)

Abbreviations: OS, Overall Survival; CD, Chengdu; GZ, Guangzhou; HR, Hazard Ratio.

^⁎P value was determined using Cox proportional-hazards model.