Gastounioti A, et al. - By using a large urban screening population, researchers studied the impact of screening mammography modality on Breast Imaging Reporting and Data System (BI-RADS) breast density assessments. Data from 24,736 individual women who received one to seven mammographic screening examinations from September 2010 to February 2017 were retrospectively analyzed. Modality interactions with ethnicity and body mass index (BMI) were observed on the assessment of breast density, with greater differences in density categorization for black women than for white women and higher BMI groups. By screening mammographic modality, categorization of breast density might vary, and this effect appears to vary by ethnicity and body mass index.