Table 3.
Multivariable Analysis of Overall Survival
| Covariate | Level | OS (Months)
|
||
|---|---|---|---|---|
| Hazard Ratio | HR P-value | Type3 P-value | ||
| Postoperative Radiation | Yes | 0.87 (0.77–0.98) | 0.021 | 0.021† |
| No | - | - | ||
|
| ||||
| Sex | Male | 1.23 (1.09–1.38) | <.001 | <.001† |
| Female | - | - | ||
| Patient Age | 1.01 (1.01–1.02) | <.001 | <.001† | |
|
| ||||
| Insurance | Not Insured | 1.29 (0.87–1.90) | 0.201 | 0.087 |
| Private Insurance | 0.90 (0.78–1.03) | 0.133 | ||
| Govt. Insurance | - | - | ||
|
| ||||
| Income | < $30,000 | 1.26 (1.03–1.53) | 0.022 | 0.028† |
| $30,000 – $34,999 | 1.25 (1.06–1.48) | 0.009 | ||
| $35,000 – $45,999 | 1.14 (0.99–1.32) | 0.075 | ||
| $46,000 + | - | - | ||
|
| ||||
| Urban/Rural | Urban/Rural | 0.83 (0.70–0.99) | 0.034 | 0.034† |
| Metro Area | - | - | ||
|
| ||||
| Histology | Squamous cell carcinomas | 1.00 (0.87–1.16) | 0.966 | 0.013† |
| Large cell carcinomas | 1.21 (0.95–1.54) | 0.130 | ||
| Adenosquamous carcinomas | 1.55 (1.16–2.07) | 0.003 | ||
| Adenocarcinomas | - | - | ||
|
| ||||
| AJCC Pathologic T stage | 4 | 1.58 (1.25–2.01) | <.001 | <.001† |
| 3 | 1.33 (1.01–1.76) | 0.042 | ||
| 2 | 1.25 (1.10–1.42) | <.001 | ||
| 0/1 | - | - | ||
|
| ||||
| Regional Nodes Positive | >=3 | 1.48 (1.30–1.68) | <.001 | <.001† |
| 1–2 | - | - | ||
|
| ||||
| Regional Nodes Examined | >9 | 0.59 (0.48–0.72) | <.001 | <.001† |
| 7–9 | 0.67 (0.54–0.84) | <.001 | ||
| 4–6 | 0.68 (0.54–0.84) | <.001 | ||
| 1–3 | - | - | ||
Abbreviations: OS: Overall Survival; HR: Hazard Ratio; AJCC: American Joint Committee on Cancer
†
Significant
Number of observations in the original data set = 2115.
Number of observations used = 1730.
Backward selection with an alpha level of removal of .20 was used. The following variables were removed from the model: Charlson/Deyo score, facility type, grade, year of diagnosis, and race.