Novel mapping methods to describe utilization of free breast cancer screening from a state program

Introduction: The National Breast and Cervical Cancer Early Detection Program (NBCCEDP) is a cancer screening program whose mission is to reduce cancer morbidities for uninsured and underinsured women. A primary activity is to connect women to breast cancer screening. The eligible population and utilization of NBCCEDP screening services have never been quantified at a sub-state level, which hampers effective program evaluation. Here, the Minnesota NBCCEDP, “Sage”, serves as a case study to demonstrate novel spatial analysis methods that depict variation of screening rates at the local level. Methods: Women who received breast cancer screening through Sage between 2011 and 2015 were geocoded (N = 74,712 screenings); analysis occurred between 2017 and 2019. We determine an eligible population using a synthetic population dataset that provides geographic residence and demographic information. We introduce a novel spatial analysis technique, spatially adaptive filters (SAFs), to create a utilization map of Sage breast screening services by Minnesota women. Results: Between 2011 and 2015, an average of 36,979 women per year were eligible for NBCCEDP breast cancer screening services, representing 3% of the Minnesota female population 40 and older. For Minnesota NBCCEDP eligible women, the state average breast cancer screening utilization rate was 37.2%, but varied considerably by local regions within the state (range 0% to 131%, SD = 18.7%). Conclusions: This geospatial model estimated screening service utilization at the local level and enables Minnesota's Sage program to target specific areas they have yet to reach. Similar programs could employ this model to direct program activities.