This dataset was created by selecting one exam per woman per calendar year and year of age. When both screening and diagnostic mammograms exist for a given woman and year, screening mammograms were preferentially selected.
This table explains how to read the data in the Risk Factor Dataset.
| Variable Name | Description | Coding |
|---|---|---|
| year | Calendar year of observation | Numerical, 2005-2017 |
| age_group_5_years | Age (years) in 5 year groups | 1 = Age 18-29 2 = Age 30-34 3 = Age 35-39 4 = Age 40-44 5 = Age 45-49 6 = Age 50-54 7 = Age 55-59 8 = Age 60-64 9 = Age 65-69 10 = Age 70-74 11 = Age 75-79 12 = Age 80-84 13 = Age >85 |
| race_eth | Race/ethnicity | 1 = Non-Hispanic white 2 = Non-Hispanic black 3 = Asian/Pacific Islander 4 = Native American 5 = Hispanic 6 = Other/mixed 9 = Unknown |
| first_degree_hx | History of breast cancer in a first degree relative | 0 = No 1 = Yes 9 = Unknown |
| age_menarche | Age (years) at menarche | 0 = Age >14 1 = Age 12-13 2 = Age <12 9 = Unknown |
| age_first_birth | Age (years) at first birth | 0 = Age < 20 1 = Age 20-24 2 = Age 25-29 3 = Age >30 4 = Nulliparous 9 = Unknown |
| BIRADS_breast_density | BI-RADS breast density | 1 = Almost entirely fat 2 = Scattered fibroglandular densities 3 = Heterogeneously dense 4 = Extremely dense 9 = Unknown or different measurement system |
| current_hrt | Use of hormone replacement therapy | 0 = No 1 = Yes 9 = Unknown |
| menopaus | Menopausal status | 1 = Pre- or peri-menopausal 2 = Post-menopausal 3 = Surgical menopause 9 = Unknown |
| bmi_group | Body mass index (kg/m2) | 1 = 10-24.99 2 = 25-29.99 3 = 30-34.99 4 = 35 or more 9 = Unknown |
| biophx | Previous breast biopsy or aspiration | 0 = No 1 = Yes 9 = Unknown |
| breast_cancer_history | Prior breast cancer diagnosis | 0 = No 1 = Yes 9 = Unknown |
| count | Frequency count of this combination of covariates | Numerical |