Table 4.

Univariate COX proportional hazards models for overall survival by country of birth

	Caribbean born		US born
	Univariable	Multivariable	Univariable	Multivariable
Variable	HR (95 % CI)	HR (95% CI)	HR (95% CI)	HR (95% CI)
Age at diagnosis (continuous)	1.03 (0.99 to 1.07)		1.03 (0.99 to 1.06)
Surgery
No (reference)	--		--	--
Yes	0.58 (0.27 to 1.21)		0.49 (0.26 to 0.93)	0.42 (0.20 to 0.89)
Hormone antagonism
No (reference)	--		--
Yes	0.37 (0.05 to 2.74)		0.47 (0.14 to 1.54)
Chemotherapy
No (reference)	--		--
Yes	1.44 (0.73 to 2.87)		1.64 (0.91 to 2.96)
Radiation
No (reference)	--		--
Yes	0.56 (0.24 to 1.30)		0.47 (0.22 to 1.01)
Tobacco use
Never/former (reference)	--		--
Current	4.27 (0.56 to 32.4)		1.07 (0.42 to 2.73)
Alcohol use
Never/former (reference)	--		--
Current	1.09 (0.26 to 4.63)		0.36 (0.09 to 1.50)
Stage of disease
Stages I and II (reference)	--	--	--	--
Stages III and IV	4.79 (2.16 to 10.62)	3.25 (1.45 to 7.31)	5.22 (2.77 to 9.82)	4.22 (2.10 to 8.51)
Insurance status
Insured (reference)	--		--
No insurance	0.97 (0.45 to 2.08)		0.91 (0.36 to 2.32)
Histologic grade
Low grade (reference)	--	--	--	--
High grade	8.72 (2.08 to 36.51)	5.57 (1.28 to 24.25)	4.36 (2.07 to 9.16)	2.23 (0.98 to 5.07)