Evaluating and comparing methods for measuring spatial access to mammography centers in Appalachia

This study evaluated spatial access to mammography centers in Appalachia using both traditional access measures and the two-step floating catchment area (2SFCA) method. Ratios of county mammography centers to women age 45 and older, driving time to nearest mammography facility, and various 2SFCA approaches were compared throughout Pennsylvania, Ohio, Kentucky, and North Carolina. Closest travel time measures favored urban areas. The 2SFCA method produced varied results depending on the parameters chosen. Appalachia areas had greater travel times to their closest mammography center. Appalachia areas in OH and NC had worse 2SFCA scores than non-Appalachia areas of the same states. A relative 2SFCA approach, the spatial access ratio method, was recommended because it helped minimize the differences between various 2SFCA approaches.