Factors affecting recall rate and false positive fraction in breast cancer screening with breast tomosynthesis - A statistical approach

•Breast density and breast cancer mainly affect the recall for breast tomosynthesis.•False recalls for breast tomosynthesis are mainly affected by breast density.•False recalls for breast tomosynthesis increase with breast density.•False recalls are 40% higher for breast tomosynthesis compared to digital mammography.

In this study, we investigate which factors affect the false positive fraction (FPF) for digital breast tomosynthesis (DBT) compared to digital mammography (DM) in a screening population by using classification and regression trees (C&RT) and binary marginal generalized linear models.The data was obtained from the Malmö Breast Tomosynthesis Screening Trial, which aimed to compare the performance of DBT to DM in breast cancer screening. By using data from the first half of the study population (7500 women), a tree with the recall probability for different groups was calculated. The effect of age and breast density on the FPF was estimated using a binary marginal generalized linear model.Our results show that breast density and breast cancer were the main factors influencing recall. The FPF is mainly affected by breast density and increases with breast density for DBT and DM.In conclusion, the results obtained with C&RT are easy to interpret and similar to those obtained using binary marginal generalized linear models. The FPF is approximately 40% higher for DBT compared to DM for all breast density categories.