Table 3.

Multivariate analysis of palliative radiotherapy.

		Relative rate of receiving palliative radiation (95% CI)
Model	Age 66-69	Age 70-74	Age 75-79	Age 80-84	Age ≥85
Unadjusted	1.00	0.89 (0.86-0.92)	0.75 (0.72-0.77)	0.58 (0.55-0.60)	0.34 (0.32-0.36)
Prior model adjusted for primary tumor site	1.00	0.89 (0.87-0.92)	0.76 (0.74-0.78)	0.61 (0.58-0.63)	0.39 (0.36-0.41)
Prior model adjusted for geography †	1.00	0.89 (0.87-0.92)	0.76 (0.73-0.78)	0.60 (0.58-0.63)	0.38 (0.36-0.41)
Prior model adjusted for patient demographics ‡	1.00	0.89 (0.86-0.91)	0.76 (0.73-0.78)	0.61 (0.59-0.63)	0.40 (0.37-0.42)
Prior model adjusted for comorbidity §	1.00	0.90 (0.87-0.92)	0.77 (0.75-0.80)	0.62 (0.60-0.65)	0.41 (0.38-0.43)
Prior model adjusted for survival time ∥	1.00	0.91 (0.89-0.94)	0.80 (0.78-0.83)	0.67 (0.64-0.69)	0.45 (0.43-0.48)
Prior model adjusted for aggressiveness of care ¥	1.00	0.93 (0.91-0.96)	0.85 (0.82-0.87)	0.75 (0.73-0.78)	0.56 (0.53-0.59)

This table represents sequentially constructed multivariate Poisson regression models.

^†Geography refers to geographic region, metropolitan area, and density of radiation oncologists.

^‡Patient demographics refer to gender, race, median income level, and year of diagnosis.

^§Comorbidity refers to the Charlson comorbidity score.

^∥Survival time refers to the time from diagnosis through death.

^¥Aggressiveness of care covariates include the aggressiveness at end-of-life score (defined in the methods), and the receipt of chemotherapy. All p-values<0.0001.