Breast density, risk level, and false-positive results

Data for women aged 50 to 74 years (A) and 65 to 74 years (B) are shown according to screening frequency and risk level (relative risk group and breast density level) using an exemplar model (Model E*). Values for all screening frequencies were compared with the scenario of no mammography screening. Values for women aged 65 to 74 years assume all women received biennial screening during ages 50 to 64 years. Dashed lines show this value for women with average density and average risk receiving biennial screening (147.7 for women aged 50 to 74 years and 105.8 for women aged 65 to 74 years). Having fewer false-positive mammograms per breast cancer death averted than this level—in other words, a value below the dashed line—would be more favorable.