Table 4.

Final Cox Proportional Hazards Model in Overall Cohort

Variable	Hazard Ratio	95% CI	P valuea
Laparoscopic Colectomy	0.902	0.776-1.050	0.1838
Female Gender	0.846	0.818-0.876	< 0.0001
Black Race	1.174	1.104-1.249	< 0.0001b
Emergent Presentation	1.419	1.325-1.519	< 0.0001
Positive Nodes	1.897	1.812-1.986	< 0.0001
Chemotherapy Receipt	3.380	2.040-5.600	< 0.0001
Chemotherapy*ln(survival time)	1.356	1.314-1.399	< 0.0001
Regional Stage	1.264	1.201-1.329	< 0.0001c
Distant Stage	5.560	5.236-5.903	< 0.0001c
Regional Stage*ln(survival time)	0.967	0.941-0.993	0.0127
Distant Stage*ln(survival time)	1.037	1.006-1.068	0.0184
Age at Dx (1-year change)	1.056	1.053-1.059	< 0.0001
Age at Dx*ln(survival time)	1.003	1.001-1.004	0.0011
Age at Dx*Chemotherapy	0.978	0.972-0.985	< 0.0001
Charlson index (1-unit change)	1.257	1.237-1.277	< 0.0001

Dx, Diagnosis.

^a Wald test.

^b Compared with white/other race.

^c Compared with localized stage.