Table 2.

A comparison of survival between ex-smokers and current smokers in the step-by-step multivariate models

	HR	95% CI	p-value
Univariate
Ex-smoker	Reference
Current smoker	0.52	0.29 – 0.95	0.033
Model containing DLco%
Ex-smoker	Reference
Current smoker	0.60	0.33 – 1.10	0.098
Dlco%	0.97	0.96 – 0.99	0.001
Model containing CPI
Ex-smoker	Reference
Current smoker	0.62	0.34 – 1.14	0.126
CPI	1.03	1.01 – 1.05	0.001
Model containing DLco % and age
Ex-smoker	Reference
Current smoker	1.32	062 – 2.72	0.472
Dlco%	0.97	0.95 – 0.98	<0.001
Age at diagnosis	1.06	1.02 – 1.10	0.001
Model containing CPI and age
Ex-smoker	Reference
Current smoker	1.63	0.75 – 3.54	0.217
CPI	1.05	1.02 – 1.07	< 0.001
Age at diagnosis	1.07	1.03 – 1.12	<0.001
Model containing DLco %, age and gender
Ex-smoker	Reference
Current smoker	1.32	063 – 2.80	0.465
Dlco%	0.97	0.95 – 0.99	<0.001
Age at diagnosis	1.06	1.03 – 1.10	0.001
Gender - female	Reference
male	1.10	0.45 – 2.69	0.831
Model containing CPI, age and gender
Ex-smoker	Reference
Current smoker	1.66	0.76 – 3.64	0.203
CPI	1.05	1.02 – 1.07	<0.001
Age at diagnosis	1.07	1.03 – 1.12	<0.001
Gender - female	Reference
male	1.22	0.51 – 2.94	0.657

HR hazard ratio, CI confidence interval, DLco diffusion capacity of carbon monoxide, CPI composite physiologic index