Table II.
Univariate and multivariate Cox regression analysis (training cohort).
| Univariate analysis | Multivariate analysis | |||||
|---|---|---|---|---|---|---|
| Variable | HR | 95% CI | P-value | HR | 95% CI | P-value |
| Age at diagnosis | 1.020 | 1.019–1.022 | <0.001 | 1.015 | 1.013–1.016 | <0.001 |
| Ethnicity | 1.477 | 1.357–1.609 | <0.001 | |||
| White | ||||||
| Black | ||||||
| Other | ||||||
| Sex | 0.612 | 0.582–0.645 | <0.001 | |||
| Male | Reference | |||||
| Female | 0.806 | 0.763–0.852 | <0.001 | |||
| Marital status | 1.260 | 1.225–1.297 | <0.001 | |||
| Married | Reference | |||||
| Single | 1.095 | 1.021–1.174 | 0.011 | |||
| DSW | 1.184 | 1.114–1.259 | <0.001 | |||
| Site | 1.393 | 1.365–1.423 | <0.001 | |||
| Head and neck | Reference | |||||
| Trunk | 0.893 | 0.832–0.958 | 0.001 | |||
| Upper limbs | 0.753 | 0.695–0.816 | <0.001 | |||
| Lower limbs | 0.866 | 0.797–0.941 | <0.001 | |||
| Other | 1.011 | 0.930–1.099 | 0.800 | |||
| AJCC stage | 3.249 | 3.183–3.316 | <0.001 | |||
| I | Reference | |||||
| II | 5.759 | 5.300–6.258 | <0.001 | |||
| III | 9.320 | 8.132–10.682 | <0.001 | |||
| IV | 19.148 | 15.089–24.299 | <0.001 | |||
| SEER stage | 4.719 | 4.594–4.847 | <0.001 | |||
| Localized | Reference | |||||
| Regional | 1.592 | 1.420–1.785 | <0.001 | |||
| Distant | 1.858 | 1.487–2.321 | <0.001 | |||
| Insurance status | 0.612 | 0.560–0.670 | <0.001 | |||
| Any medicaid | Reference | |||||
| Insured | 0.762 | 0.698–0.832 | <0.001 | |||
| Uninsured | 1.201 | 1.039–1.388 | 0.013 | |||
| Median family income, USD | 0.746 | 0.705–0.790 | <0.001 | |||
| 24,880-50,000 | Reference | |||||
| 50,060-98,030 | 0.916 | 0.843–0.994 | 0.035 | |||
| 100,190-125,990 | 0.800 | 0.713–0.896 | <0.001 | |||
HR, hazard ratio; CI, confidence interval; SEER, Surveillance, Epidemiology, and End Results; AJCC, American Joint Committee on Cancer; USD, United states dollar.