NHS development cohort | NHS validation cohorta | BWHS (Crude) | BWHS (Age-standardized)a | |
---|---|---|---|---|
N | 55,553 | 27,777 | 17,380 | 17,380 |
Factors in our final model | ||||
Age, mean (SD) | 70.1 (7.0) | 70.2 (7.0) | 63.7 (6.7) | – |
55–59 years, % | 7.1 | 6.7 | 36.5 | – |
60–64 years, % | 21.4 | 21.5 | 28.3 | – |
65–69 years, % | 22.4 | 22.3 | 17.1 | – |
70–74 years, % | 20.9 | 20.8 | 9.9 | – |
75–79 years, % | 18.1 | 18.8 | 5.8 | – |
80+ years, % | 10.1 | 10.0 | 2.4 | – |
Highest self-reported Body Mass Index (BMI) in past 10 years kg/m2, mean (SD) | 28.1 (5.7) | 28.1 (5.8) | 32.1 (7.0) | 31.6 (6.5) |
Highest self-reported BMI in past 10 years | ||||
< 20 kg/m2, % | 2.7 | 2.7 | 0.5 | 0.5 |
20–22.4 kg/m2, % | 10.9 | 11.2 | 3.0 | 3.0 |
22.5–24.9 kg/m2, % | 19.1 | 19.4 | 8.5 | 9.2 |
25–29.9 kg/m2, % | 36.5 | 36.3 | 31.6 | 33.7 |
30–34.9 kg/m2, % | 19.5 | 18.9 | 28.3 | 28.0 |
35–39.9 kg/m2, % | 7.1 | 7.3 | 14.5 | 13.5 |
40+ kg/m2, % | 4.1 | 4.1 | 12.6 | 10.7 |
Unknown, % | 0.1 | 0.2 | 1.0 | 1.3 |
Average alcohol use per day (highest average use in past 10 years)b | ||||
None, % | 37.0 | 37.0 | 50.4 | 54.1 |
1–4.9 g/day, % | 22.5 | 22.7 | 26.0 | 23.9 |
5–14.9 g/day, % | 17.5 | 17.1 | 13.7 | 12.6 |
15+ g/day, % | 13.1 | 13.4 | 9.9 | 9.3 |
Unknown, % | 10.0 | 9.8 | – | – |
Cigarette use | ||||
Never | 44.7 | 44.8 | 53.4 | 50.5 |
Current | 7.7 | 7.9 | 10.1 | 8.0 |
Past | 47.4 | 47.1 | 36.4 | 41.5 |
Unknown | 0.2 | 0.2 | – | – |
Limited from walking several blocksc | ||||
Not at all | 61.8 | 61.5 | – | – |
A little or a lot | 32.8 | 33.1 | – | – |
Unknown, % | 5.4 | 5.4 | – | – |
Limited in bathing or dressing oneselfc | ||||
Not at all | 88.2 | 87.9 | – | – |
A little or a lot | 6.5 | 6.8 | – | – |
Unknown, % | 5.3 | 5.3 | – | – |
Usual walking pace outdoors | ||||
Unable to walkc | 2.6 | 2.8 | – | – |
Slow or average (less than 3 mph) | 73.1 | 72.6 | 62.0 | 65.1 |
Brisk/very brisk (≥ 3 mph) | 19.7 | 20.0 | 27.5 | 23.3 |
Unknown, % | 4.6 | 4.6 | 10.6 | 11.6 |
High Blood pressured | 60.3 | 60.3 | 68.7 | 75.4 |
Depression | 20.4 | 20.5 | 22.2 | 19.4 |
Hip fracture | 2.1 | 2.2 | 0.8 | 1.1 |
Parkinson’s disease | 0.7 | 0.6 | 0.2 | 0.3 |
Myocardial infarction | 5.5 | 5.7 | 4.3 | 6.5 |
Congestive heart failure | 3.3 | 3.4 | 3.2 | 4.6 |
Stroke/transient ischemic attack | 7.5 | 7.5 | 4.2 | 5.7 |
Emphysema/Asthma | 18.6 | 18.5 | 18.3 | 18.0 |
Diabetes | 12.2 | 11.7 | 24.2 | 28.5 |
Dementia | 1.2 | 1.2 | 0.2 | 0.5 |
Kidney disease | 0.5 | 0.6 | 1.9 | 2.3 |
Cancer (excluding non-melanomatous skin cancers) | 12.3 | 12.2 | 5.7 | 7.4 |
Age at menopause (years) | ||||
< 45, % | 10.8 | 10.4 | 19.3 | 21.2 |
45–49, % | 23.4 | 23.9 | 20.1 | 19.2 |
50–54, % | 56.1 | 56.2 | 27.4 | 25.9 |
55+, % | 8.8 | 8.5 | 8.3 | 10.6 |
Hysterectomy, age unknown, %e | – | – | 22.2 | 21.9 |
Unknown, % | 1.0 | 1.0 | 2.7 | 1.2 |
Mammogram in past 2 yearsf | ||||
No | 12.1 | 12.2 | 14.0 | 15.2 |
Yes | 79.4 | 79.5 | 86.0 | 84.8 |
Unknown | 8.5 | 8.3 | – | – |
Number of breast biopsies | ||||
0, % | 73.2 | 73.2 | 67.0 | 65.7 |
1, % | 23.5 | 23.6 | 21.3 | 21.3 |
2+, % | 3.3 | 3.2 | 11.7 | 13.1 |
Postmenopausal hormone use | ||||
Never, % | 22.5 | 22.9 | 40.7 | 37.5 |
Current estrogen plus progestin user < 5 years, % | 0.4 | 0.5 | 0.7 | 0.2 |
Current estrogen plus progestin user 5 + years, % | 2.7 | 2.7 | 1.1 | 0.8 |
Current estrogen-alone user < 5 years, % | 0.9 | 0.8 | 1.6 | 0.7 |
Current estrogen-alone user 5 + years, % | 9.4 | 9.1 | 6.3 | 5.6 |
Past estrogen plus progestin user < 5 years, % | 14.9 | 14.9 | 12.8 | 12.5 |
Past estrogen plus progestin user 5 + years, % | 15.8 | 16.1 | 5.6 | 7.4 |
Past estrogen-alone user < 5 years, % | 7.1 | 7.2 | 12.2 | 12.2 |
Past estrogen-alone user 5 + years, % | 13.8 | 13.8 | 13.8 | 18.1 |
Unknown, % | 12.6 | 12.2 | 5.3 | 4.8 |
Age at first birth (years) and parityg | ||||
Nulliparous | 5.3 | 5.4 | 16.0 | 12.7 |
< 25, 1–2 children | 14.2 | 13.9 | 32.2 | 35.4 |
< 25, 3+ children | 35.2 | 34.9 | 27.8 | 28.3 |
25–29, 1–2 children | 14.8 | 15.3 | 11.9 | 10.8 |
25–29, 3+ children | 20.1 | 20.3 | 2.9 | 4.0 |
30+, 1–2 children | 5.8 | 5.8 | 7.1 | 6.3 |
30+, 3+ children | 2.8 | 2.8 | 0.5 | 0.6 |
Unknown | 1.8 | 1.7 | 1.6 | 1.9 |
Number of first-degree relatives with history of breast cancer and age at diagnosish | ||||
None, % | 82.1 | 81.9 | 80.1 | 79.8 |
1 and age < 50, % | 4.3 | 4.1 | 3.8 | 4.2 |
1 and age 50+, % | 11.6 | 11.8 | 14.2 | 14.0 |
2+ and at least one age < 50, % | 1.0 | 1.1 | 0.6 | 0.7 |
2+ and age 50+, % | 1.1 | 1.1 | 1.3 | 1.3 |
Outcomes | ||||
Breast cancer in 5-year follow-up, % | 1.7 | 1.7 | 1.7 | 1.8 |
Breast cancer in 10-year follow-up, % | 3.1 | 3.2 | 3.1 | 3.2 |
Breast cancer death in 5-year follow-up, % | 0.1 | 0.1 | 0.2 | 0.2 |
Breast cancer death in 10-year follow-up, % | 0.3 | 0.2 | 0.4 | 0.6 |
Non-breast cancer death 5-year follow-up, % | 7.7 | 8.0 | 4.5 | 8.1 |
Non-breast cancer death 10-year follow-up, % | 20.1 | 20.6 | 11.1 | 19.7 |
Not included in model | ||||
Race/ethnicity | ||||
Non-Hispanic White, % | 96.2 | 96.3 | 0.0 | 0.0 |
Non-Hispanic Black, % | 1.8 | 1.6 | 99.1 | 99.9 |
Hispanic,% | 0.9 | 0.9 | 0.9 | 0.1 |
Asian, Pacific Islander % | 0.8 | 0.9 | 0.0 | 0.0 |
Native American, % | 0.2 | 0.2 | 0.0 | 0.0 |
Education (years)i | ||||
< 12 | – | – | 2.7 | 4.0 |
12 | – | – | 16.4 | 19.1 |
13–15 | – | – | 27.8 | 26.2 |
16 | 91.7 | 91.7 | 19.5 | 17.1 |
17+ | 8.4 | 8.4 | 33.6 | 33.5 |
Unknown | 0.0 | 0.0 | 0.1 | 0.1 |
Predicted mammographic densityj | n = 35,073 | n = 17,482 | ||
Higher than median (≥ 24.7% dense) | 50.0 | 50.1 | – | – |
Lower than median (< 24.7% dense) | 50.0 | 49.9 | – | – |