Appendix Table 3.
Characteristics of Study Population, by Study Cohort
| Variable | San Francisco Mammography Registry Control Participants (n = 2603) |
Mayo Clinic Control Participants (n = 1806) |
|---|---|---|
| Mean age (SD), y | 58.3(11.9) | 61.3(11.4) |
| Mean body mass index (SD), kg/m2 | 24.9 (5.1) | 28.6 (6.5) |
| Median dense breast volume (IQR), mL* | 50.7 (36.3–71.9) | 52.5 (39.7–70.6) |
| Family history of breast cancer, n (%)† | 453 (17.4) | 384(21.4) |
| History of breast biopsy, n (%) | 315 (12.1) | 473 (26.2) |
| Race/ethnicity, n (%) | ||
| White | 1768 (67.9) | 1758 (97.3) |
| Asian | 549 (21.1) | 21 (1.2) |
| Black | 87 (3.3) | 2 (0.1) |
| Hispanic | 101 (3.9) | 9 (0.5) |
| Other | 98 (3.8) | 16 (0.9) |
| Clinical BI-RADS density, n (%) | ||
| Almost entirely fatty | 369 (14.2) | 432 (23.9) |
| Scattered fibroglandular densities | 1018 (39.1) | 746 (41.3) |
| Heterogeneously dense | 939 (36.1) | 530 (29.3) |
| Extremely dense | 277 (10.6) | 98 (5.4) |
| Automated BI-RADS density, n (%)* | ||
| Almost entirely fatty | 448 (17.2) | 519 (28.7) |
| Scattered fibroglandular densities | 760 (29.2) | 635 (35.2) |
| Heterogeneously dense | 876 (33.7) | 477 (26.4) |
| Extremely dense | 519 (19.9) | 175 (9.7) |
| BCSC 5–y risk, n (%) | ||
| Low (G%-G.99%) | 952 (36.6) | 421 (23.3) |
| Average (1.GG%–1.66%) | 756 (29) | 454(25.1) |
| Intermediate (1.67%–2.49%) | 583 (22.4) | 527 (29.2) |
| High (2.5G%–3.99%) | 239 (9.2) | 289 (16) |
| Very high (≥4.GG%) | 73 (2.8) | 115(6.4) |
BCSC = Breast Cancer Surveillance Consortium; BI-RADS = Breast Imaging Reporting and Data System; IQR = interquartile range.
*
Measured with Volpara software (Volpara Solutions).
†
Mother, sister, or daughter with breast cancer.