Table 3.

Cox Proportional Hazards Model for Overall Survival in Patients < 45 Years with pT1 Differentiated Thyroid Cancer, NCDB 1998–2012

Variable	Hazard ratio	CI		p-Value
pT1a vs. pT1b	1.18	0.98	1.42	0.09
Demographic factors
Patient age, per 10 years	1.70	1.47	1.96	<0.001
Female sex	0.50	0.41	0.61	<0.001
Race/ethnicity
White*
Black	1.38	1.05	1.82	0.02
Asian	0.52	0.30	0.90	0.02
Other	0.45	0.15	1.42	0.17
Annual household income
<$35,000*
≥$35,000	0.71	0.60	0.84	<0.001
Insurance status
Uninsured*
Private	0.60	0.44	0.83	0.002
Government	2.18	1.55	3.06	<0.001
Treatment characteristics
Total thyroidectomy	0.98	0.80	1.20	0.85
Positive surgical margin	1.19	0.83	1.71	0.35
Metastatic lymph nodes	1.50	1.21	1.87	<0.001
Distant metastases	1.16	0.16	8.31	0.88
RAI	0.70	0.58	0.84	<0.001

^*Reference variable.