Table 3.

Cox proportional hazard models for overall survival

Prognostic factor	Overall cohort		Weighted cohort
	P	Hazard ratio (CI)	P	Hazard ratio (CI)
Univariate
Age (>60 vs ≤60 y)	.30	1.20 (0.85–1.69)	.06	1.27 (0.99–1.63)
Gender (female vs male)	.80	0.96 (0.69–1.33)	.77	0.97 (0.76–1.23)
Race (white vs other)	.38	0.85 (0.59–1.22)	.004	0.67 (0.52–0.88)
KPS (≥80 vs <80)	.07	0.66 (0.42–1.04)	.12	0.75 (0.51–1.08)
% Weight loss (<10% vs ≥10%)	.48	0.89 (0.64–1.23)	.13	0.83 (0.65–1.06)
Baseline hemoglobin (>12 vs ≤12g/dL)	.29	0.82 (0.58–1.18)	.53	0.92 (0.71–1.19)
Tumor location (head vs other)	.90	1.02 (0.73–1.42)	.54	1.08 (0.85–1.37)
Induction chemotherapy (gemcitabine vs others)	.54	1.17 (0.71–1.92)	.53	1.12 (0.78–1.61)
Concurrent chemotherapy (capecitabine vs others)	.18	0.74 (0.47–1.15)	.06	0.74 (0.54–1.01)
Change in CA19-9 after induction chemotherapy (>34% vs ≤ 34%)	.45	0.87 (0.62–1.24)	.69	1.06 (0.81–1.38)
BED (>70 vs ≤70 Gy)	.03	0.63 (0.41–0.95)	.01	0.71 (0.56–0.90)
Multivariate efull model
Age (>60 vs ≤60 y)			.002	1.56 (1.18–2.08)
Race (white vs other)			.002	0.64 (0.48–0.85)
KPS (≥80 vs <80)	.15	0.71 (0.45–1.13)	.12	0.74 (0.50–1.08)
% Weight loss (<10% vs ≥10%)			.94	1.01 (0.78–1.30)
Concurrent chemotherapy (capecitabine vs others)	.17	0.72 (0.45–1.15)	.01	0.65 (0.47–0.91)
BED (>70 vs ≤70 Gy)	.02	0.59 (0.38–0.91)	.02	0.75 (0.59–0.94)
Multivariate ereduced model
Age (>60 vs ≤60 y)			.003	1.52 (1.16–2.00)
Race (white vs other)			.002	0.64 (0.48–0.85)
Concurrent chemotherapy (capecitabine vs others)			.01	0.64 (0.46–0.89)
BED (>70 vs ≤70 Gy)	.03	0.63 (0.41–0.95)	.01	0.74 (0.58–0.94)

Abbreviations: BED = biologically effective dose; CI = 95% confidence interval; KPS = Karnofsky performance status.