Table 1.

Patient Characteristics according to age.

	Age (years)
Characteristic	66-69 (n=11,749)	70-74 (n=15,688)	75-79 (n=15,707)	80-84	>85 (n=8,431)
Year of diagnosis
2000	11%	12%	12%	11%	11%
2001	11%	13%	12%	11%	11%
2002	12%	13%	12%	13%	11%
2003	13%	13%	13%	12%	12%
2004	14%	13%	14%	14%	14%
2005	14%	13%	13%	14%	14%
2006	13%	12%	13%	13%	14%
2007	12%	11%	11%	12%	14%
Primary tumor origin
Lung	73%	72%	69%	61%	47%
Breast	5%	5%	5%	6%	8%
Prostate	6%	7%	8%	11%	16%
Colorectal	16%	17%	18%	22%	29%
Gender
Male	57%	55%	53%	50%	46%
Female	43%	45%	47%	50%	54%
Race
White	83%	84%	84%	85%	85%
Black	12%	10%	9%	8%	9%
Other	5%	6%	7%	7%	6%
Marital status
Married	54%	53%	50%	44%	31%
Other	46%	47%	50%	56%	69%
Charlson comorbidity score
0	55%	50%	48%	47%	48%
1	26%	28%	27%	28%	27%
2	10%	12%	14%	14%	13%
≥3	9%	10%	11%	12%	12%
Median income
Bottom quintile	22%	21%	20%	19%	18%
2nd quintile	21%	20%	20%	20%	19%
3rd quintile	20%	20%	20%	20%	20%
4th quintile	19%	19%	21%	20%	21%
Top quintile	18%	19%	20%	21%	22%
Geographic region
East	19%	23%	24%	25%	26%
Midwest	16%	16%	16%	16%	16%
South	25%	22%	20%	18%	17%
West	40%	39%	40%	41%	42%
Metropolitan area
Yes	81%	82%	84%	85%	85%
No	19%	18%	16%	15%	15%
Density of radiation oncologists (per 1,000 square miles)
<1	26%	24%	22%	20%	19%
1-10	29%	29%	28%	28%	27%
11-20	10%	10%	11%	12%	12%
21-30	8%	8%	9%	9%	10%
31-40	9%	9%	10%	10%	12%
≥40	18%	19%	20%	21%	21%
Aggressiveness of care composite score
0	52%	53%	55%	59%	63%
1	18%	19%	18%	18%	18%
≥2	30%	28%	26%	23%	19%
Treated with chemotherapy
Yes	58%	53%	46%	35%	21%
No	42%	47%	54%	65%	79%