Table 3.

Multivariate Cox regression model survival analysis using first QOL assessment

Effect	Hazard ratio	95% hazard ratio confidence limits		P-value
QOL (vs. > 50)1
Deficit (QOL ≤ 50)	1.841	1.440	2.354	<0.0001
Age, years (vs. ≥ 80)1
<60	0.395	0.278	0.562	<0.0001
60–69.999	0.489	0.351	0.680	<0.0001
70–79.999	0.795	0.582	1.085	0.1479
Sex (vs. male)1
Female	0.782	0.639	0.957	0.0169
ECOG performance status (vs. 2, 3, 4)1
0, 1	0.448	0.344	0.585	<0.0001
Smoking cessation (vs. kept smoking)1
Quit	0.496	0.336	0.733	0.0004
Tumor size (>2 cm)1
≤2 cm	0.702	0.563	0.874	0.0016
Regional nodal involvement (vs. metastasis in contralateral mediastinal)1
No nodal metastases	0.259	0.156	0.428	<0.0001
In ipsilateral peribronchial and/or ipsilateral hilar nodes	0.402	0.231	0.701	0.0013
In ipsilateral mediastinal and/or subcarinal nodes	0.574	0.345	0.954	0.0323
Distant metastasis (vs. presence)1
Absence	0.274	0.204	0.368	<0.0001

QOL, quality of life; ECOG, Eastern Cooperative Oncology Group.

¹Reference group.