Table 3.

Final Proportional Hazards Model for Lung Cancer Specific Survival

Variable	HR	95%CI	P>X2
Treatment
Lobectomy (Baseline)	1.00	--	--
Sublobar Resection	1.50	1.29 – 1.75	<.001
SABR	1.44	1.03 – 2.02	0.03
Age
66–69 (Baseline)	1.00	--	--
70–74	1.29	1.09 – 1.52	<.001
75–79	1.37	1.16 – 1.62	<.001
≥80	1.66	1.40 – 1.98	<.001
Sex
Male (Baseline)	1.00	--	--
Female	0.75	0.67 – 0.83	<.001
Educational Attainment
1st Quartile (0 – 10%)	1.00	--	--
2nd Quartile (10 – 17%)	1.15	0.99 – 1.33	0.07
3rd Quartile (17 – 27%)	1.21	1.04 – 1.40	0.01
4th Quartile (>27%)	1.30	1.11 – 1.51	0.00
COPD
No (Baseline)	1.00	--	--
Yes	1.25	1.16 – 1.34	<.001
Charleson Comorbidity Score Ex. COPD
0 (Baseline)	1.00	--	--
1	1.03	0.90 – 1.17	0.69
≥2	1.30	1.13 – 1.49	<.001
Oxygen Supplementation
No (Baseline)	1.00	--	--
Yes	1.35	1.17 – 1.55	<.001
T-Stage
T1A (0.0 – 2.0 cm) (Baseline)	1.00	--	--
T1B (2.1 – 3.0 cm)	1.30	1.15 – 1.47	<.001
T2A (3.1 – 5.0 cm)	1.60	1.40 – 1.83	<.001
Histology
NSCLC, NOS (Baseline)	1.00	--	--
Adenocarcinoma	0.82	0.67 – 1.01	0.06
Squamous carcinoma	0.95	0.77 – 1.17	0.63
Large cell	0.99	0.72 – 1.35	0.94
Mediastinal Sampling
Not Performed (Baseline)	1.00	--	--
Performed	0.78	0.78 – 0.78	<.001
Year of Diagnosis
2003 (Baseline)	1.00	--	--
2004	0.92	0.79 – 1.08	0.31
2005	0.96	0.81 – 1.13	0.59
2006	0.90	0.75 – 1.08	0.26
2007	0.76	0.62 – 0.94	0.01
2008	0.76	0.59 – 0.97	0.03
2009	0.55	0.36 – 0.84	0.01

Abbreviations: HR, hazard ratio; CI, confidence interval; SABR, stereotactic ablative radiation; Ex, excluding; NSCLC, NOS, non-small cell lung cancer, not otherwise specified