Table 3. Cox Proportional Hazards Model for Overall Survival Duration and PHQ-9 Depression (Continuous).

Effect	Full model				Reduced model
	HR	95% LB	95% UB	p value	HR	95% LB	95% UB	p value
Age	1.0	0.9	1.1	0.9
Female	1.1	0.2	5.9	0.9
Chemotherapy (referent: none/neoadjuvant)
Concurrent only	1.2	0.3	5.9	0.8
Neoadjuvant and concurrent	1.1	0.2	5.9	0.9
Excessive alcohol use	3.9	0.4	37.5	0.2
Smoking status (referent: never)
Former	1.9	0.5	8.3	0.4
Recent	5.3	0.5	63.2	0.2
Current	3.9	0.8	18.5	0.1
Tumor size (referent: not T4/N3/N2c)
Any N3/N2c	2.6	0.6	12.3	0.2
Any T4	1.8	0.4	9.5	0.5
Total comorbidities	1.3	0.8	2.1	0.3	1.4	1.0	2.0	0.070
PHQ-9 Depression (continuous)	1.1	1.0	1.2	0.040	1.1	1.0	1.2	0.010

HR, hazard ratio; UB, upper bound; LB, lower bound. Boldface indicates statistical significance.