Table 3. Univariate and multivariate analysis of factors predictive of overall survival for all patients.
| Characteristics | Univariate analysis | Multivariate analysis | |||||
|---|---|---|---|---|---|---|---|
| Hazard ratio | 95% confidence interval | P value | Hazard ratio | 95% confidence interval | P value | ||
| Group | |||||||
| Advanced radiation technique | 1 (reference) | − | − | − | − | − | |
| 3D conformal radiation | 0.972 | 0.877–1.079 | 0.597 | − | − | − | |
| Age | |||||||
| <60 | 1 (reference) | − | − | 1 (reference) | − | − | |
| 60–70 | 1.055 | 0.940–1.184 | 0.365 | 1.067 | 0.951–1.199 | 0.270 | |
| >70 | 1.233 | 1.066–1.425 | 0.005 | 1.242 | 1.074–1.436 | 0.004 | |
| Sex | |||||||
| Male | 1 (reference) | − | − | 1 (reference) | − | − | |
| Female | 0.838 | 0.723–0.971 | 0.019 | 0.834 | 0.20–0.967 | 0.016 | |
| Race | |||||||
| White | 1 (reference) | − | − | − | − | − | |
| African American | 0.970 | 0.727–1.293 | 0.834 | − | − | − | |
| Hispanic | 0.758 | 0.497–1.155 | 0.197 | − | − | − | |
| Other/not recorded | 0.845 | 0.571–1.228 | 0.377 | − | − | − | |
| Histology | |||||||
| Adenocarcinoma | 1 (reference) | − | − | − | − | − | |
| Squamous cell | 0.956 | 0.834–1.096 | 0.523 | − | − | − | |
| cT stage | |||||||
| T1b | 1 (reference) | − | − | − | − | − | |
| T2 | 1.026 | 0.589–1.789 | 0.927 | − | − | − | |
| T3 | 1.267 | 0.733–2.189 | 0.396 | − | − | − | |
| T4a | 1.810 | 0.894–3.664 | 0.099 | − | − | − | |
| pN stage | |||||||
| N0 | 1 (reference) | − | − | 1 (reference) | − | − | |
| N1 | 1.107 | 0.990–1.237 | 0.075 | 1.131 | 1.011–1.266 | 0.032 | |
| N2-3 | 1.280 | 1.057–1.550 | 0.011 | 1.315 | 1.086–1.594 | 0.005 | |
| Charlson Deyo score | |||||||
| 0 | 1 (reference) | − | − | 1 (reference) | − | − | |
| 1 | 1.107 | 0.974–1.258 | 0.120 | 1.092 | 0.961–1.242 | 0.177 | |
| 2 | 1.325 | 1.052–1.670 | 0.017 | 1.312 | 1.040–1.655 | 0.022 | |
| Tumor location | |||||||
| Cervical/upper | 1 (reference) | − | − | − | − | − | |
| Thoracic/middle | 0.839 | 0.531–1.326 | 0.453 | − | − | − | |
| Abdominal/lower | 0.857 | 0.556–1.321 | 0.485 | − | − | − | |
| Overlapping | 0.916 | 0.563–1.490 | 0.724 | − | − | − | |
| Facility type | |||||||
| Non academic | 1 (reference) | − | − | 1 (reference) | − | − | |
| Academic | 0.835 | 0.753–0.926 | 0.001 | 0.827 | 0.745–0.917 | <0.0001 | |
| Insurance | |||||||
| Medicaid | 1 (reference) | − | − | − | − | − | |
| Private | 0.888 | 0.693–1.137 | 0.345 | − | − | − | |
| Medicare | 1.109 | 0.865–1.422 | 0.415 | − | − | − | |
| Not insured | 1.135 | 0.760–1.693 | 0.536 | − | − | − | |
| Income | |||||||
| <$46,000 | 1 (reference) | − | − | 1 (reference) | − | − | |
| $46,000+ | 0.855 | 0.770–0.949 | 0.003 | 0.859 | 0.773-0.954 | 0.005 | |
| Year of diagnosis | |||||||
| 2004–2008 | 1 (reference) | − | − | − | − | − | |
| 2009–2013 | 1.015 | 0.901–1.144 | 0.801 | − | − | − | |
| Distance from facility | |||||||
| ≤20 miles | 1 (reference) | − | − | − | − | − | |
| >20 miles | 1.003 | 0.903–1.115 | 0.949 | − | − | − | |
| Region | |||||||
| Northeast | 1 (reference) | − | − | − | − | − | |
| Southeast | 1.144 | 0.991–1.320 | 0.066 | − | − | − | |
| Southwest | 0.944 | 0.647–1.378 | 0.766 | − | − | − | |
| Midwest | 1.036 | 0.904–1.186 | 0.613 | − | − | − | |
| West | 0.923 | 0.773–1.102 | 0.375 | − | − | − | |