Table 2.

Characteristics of Cohort and Use of Mammography, Medicare 2004–2005

	N	Percent of Cohort	Percent With Mammogram	Adjusted OR	(95% CI)
County mammography capacity
Inadequate	112,676	12.6	38.0	0.86	(0.85 – 0.87)
Adequate	779,253	87.4	40.5	Reference	-
Age group
65–69 years	164,037	18.4	56.0	Reference	-
70–74 years	201,853	22.6	52.2	0.83	(0.82 – 0.85)
75–79 years	197,917	22.2	44.3	0.59	(0.59 – 0.60)
80–84 years	164,747	18.5	31.7	0.34	(0.34 – 0.35)
80+ years	163,375	18.3	12.9	0.11	(0.11 – 0.11)
Race
White	789,372	88.5	41.0	Reference	-
Black	69,629	7.8	34.8	0.74	(0.73 – 0.75)
Hispanic	11,716	1.3	32.1	0.66	(0.64 – 0.69)
Asian	10,033	1.1	31.0	0.54	(0.52 – 0.57)
Other/Unknown	11,539	1.3	34.3	0.67	(0.65 – 0.70)
Charlson comorbidity score
0	797,780	89.4	41.8	Reference	-
1	46,351	5.2	31.1	0.69	(0.68 – 0.71)
≥2	47,798	5.4	21.2	0.39	(0.38 – 0.40)
Primary care visit in past 2 years
Yes	815,393	91.4	42.5	5.05	(4.94 – 5.16)
No	76,536	8.6	15.1	Reference	-

Percent of Cohort gives the distribution of each characteristic within the cohort. Percent with Mammogram gives the percent of women in each row with a claim for a mammogram during the study period.

Adjusted OR: Odds ratio for impact of characteristic on odds of recent mammogram, adjusted for other characteristics in table.

Inadequate county mammography capacity was defined as <1.2 mammography machines per 10,000 women age 40+ in the county of residence.