Table 1.

Baseline characteristics of participants by mammography screening frequency, (N=5,930), Wisconsin Women’s Health Study, 1995-2007

	Annual Frequency of Mammography Screening
Characteristics	Total % (N=5,930)	0 Times % (N=596)	< 0.5 Times % (N=968)	0.5 – 0.9 Times % (N=894)	≥ 1 Times % (N=3,472)	P
Age, Years
50–59	49.9	46.8	50.5	55.6	48.8
60–69	47.0	48.2	45.4	40.2	49.0
≥ 70	3.1	5.0	4.1	4.3	2.1	< 0.00001
Driving Time to Closest Mammography Facility, Minutes
< 5	27.4	27.5	27.5	25.6	27.8
5 – 10	31.7	30.2	31.2	31.8	32.1
11–20	29.7	29.7	28.8	30.8	29.6
> 20	11.2	12.6	12.5	11.9	10.4	0.61
Number of Mammography Facilities within 10km Radius, N
0	28.1	31.0	31.6	28.6	26.4
1 – 2	29.8	33.4	28.5	29.6	29.5
3	7.8	6.5	7.2	6.3	8.6
> 3	34.4	29.0	32.6	35.5	35.5	0.0014
Number of Mammography Machines per 10,000 Women Aged 40+ in County, N
0 – 1	24.6	29.2	26.0	26.0	23.0
2 – 3	42.9	43.3	42.4	42.8	43.0
> 3	32.5	27.5	31.6	31.2	34.0	0.0070
Race/Ethnicity
White, Non-Hispanic	95.8	94.3	95.1	94.7	96.5
Other	4.2	5.7	4.9	5.3	3.5	0.010
Menopausal Status
Premenopausal	14.2	16.4	18.2	18.6	11.6
Postmenopausal	85.8	83.6	81.8	81.4	88.4	< 0.00001
Family History of Breast Cancer
Yes	16.4	12.2	13.8	15.0	18.1
No	83.6	87.8	86.2	85.0	81.9	0.000098
Postmenopausal Hormone Use
Never	53.1	84.9	70.7	57.6	41.6
Ever	46.9	15.1	29.3	42.4	58.4	< 0.00001
Family Income
≤ 30,000	33.0	53.5	41.4	32.0	27.4
$30,001 – 50,000	30.2	25.8	29.2	29.1	31.5
$50,001 – 100,000	27.9	16.9	24.4	27.3	30.8
> $100,000	8.9	3.7	5.0	11.6	10.2	< 0.00001
Education
No High School Degree	7.3	15.4	8.4	7.5	5.6
High School Degree	42.8	49.8	42.7	38.9	42.6
Some College	26.6	23.3	29.0	28.4	26.0
College Degree	23.3	11.4	19.9	25.2	25.8	< 0.00001
Urbanicity
Urban	64.2	56.4	62.1	65.2	65.8
Rural	35.8	43.6	37.9	34.8	34.2	0.000063