Table 4.
Cox Regression Proportional Hazards Model
| Variable | HR | p-value | 95% Confidence Interval | |
|---|---|---|---|---|
| Lower | Higher | |||
| Age | 1.05 | < 0.001 | 1.03 | 1.07 |
| Race | ||||
| White | REF | |||
| Black | 1.29 | 0.502 | 0.62 | 2.69 |
| Other | 0 | 0.979 | 0 | . |
| Sex | ||||
| Male | REF | |||
| Female | 0.92 | 0.803 | 0.47 | 1.79 |
| Primary Site | ||||
| Oral Cavity | REF | |||
| Oropharynx | 1.40 | 0.369 | 0.68 | 2.89 |
| Clinical N Stage | ||||
| N0 | REF | |||
| N1 | 0.87 | 0.802 | 0.30 | 2.57 |
| N2 | 2.80 | 0.015 | 1.22 | 6.43 |
| N3 | 1.47 | 0.665 | 0.26 | 8.26 |
| Nx | 1.37 | 0.777 | 0.16 | 12.07 |
| Grade | ||||
| Well Differentiated | REF | |||
| Moderately Differentiated | 2.11 | 0.099 | 0.87 | 5.11 |
| Poorly Differentiated | 4.10 | 0.003 | 1.63 | 10.31 |
| Undifferentiated | 4.25 | 0.017 | 1.29 | 13.99 |
| Neck Dissection | ||||
| No ND | REF | |||
| ND Performed | 1.52 | 0.269 | 0.73 | 3.18 |
| Treatment Regimen | ||||
| No Treatment | REF | |||
| Surgery Only | 0.22 | 0.013 | 0.07 | 0.73 |
| Radiation Only | 0.66 | 0.549 | 0.17 | 2.58 |
| Surgery with aRT | 0.11 | 0.001 | 0.03 | 0.39 |
| Surgery with aCRT | 0.37 | 0.139 | 0.10 | 1.38 |
| Chemotherapy only | 4.23 | 0.157 | 0.57 | 31.23 |