Table 4.

Difference in Lung Cancer Rates Between Veterans and Non-Veterans in the Women’s Health Initiative

Model a	Non-Veterans		Veterans		HR a	95% CI		p Value
	Total N	Lung cancer	Total N	Lung cancer		LB	UB
Age adjusted	140,952	2,766	3,695	98	1.24	1.01	1.52	.04
Age and smoking adjusted b	136,045	2,657	3,525	95	1.06	0.86	1.30	.59
Age, smoking, and region adjusted b,c	136,045	2,657	3,525	95	1.05	0.86	1.29	.63
Age, smoking, region, race, income, education, and study arm adjusted d	126,027	2,472	3,308	91	1.07	0.87	1.33	.51

Notes: CI = confidence interval; HR = hazard ratio; LB = lower bound; UB = upper bound.

^a All analyses stratified by age categories (<59, 60–69, 70+) because of evidence of violation of the proportional hazards assumption for age.

^b Pack years of smoking, continuous.

^c Pack years of smoking, continuous; region, nominal.

^d Pack years of smoking, continuous; region, nominal; race, nominal; income, ordinal; education, ordinal; study arm, nominal; among Observational Study participants only.