This study examines temporal trends in geographic disparities in small-area breast cancer incidence and mortality from 1988 to 2005. The researchers analyzed data from 200 counties using the Surveillance, Epidemiology, and End Results (SEER) Program to assess five breast cancer screening indicators: in situ breast cancer, stage I breast cancer, lymph-node positive breast cancer, locally advanced breast cancer, and breast cancer mortality. They used hierarchical Bayesian spatiotemporal methods to calculate absolute and relative geographic disparities and their changes over time. Results showed that for in situ breast cancer, absolute disparity increased by 93.7%, while relative disparity decreased by 61.5%. For stage I breast cancer, both absolute and relative disparity declined. Lymph-node positive breast cancer saw a 37.9% decline in absolute disparity and a 17.6% decline in relative disparity. Locally advanced breast cancer had a 66.5% decline in absolute disparity and a 17.8% decline in relative disparity. Breast cancer mortality also showed a 60.5% decline in absolute disparity and a 19.8% decline in relative disparity. The study concludes that geographic disparities in all breast cancer indicators except in situ breast cancer narrowed over time. Progress has been made in reducing geographic disparities in breast cancer outcomes, particularly in advanced-stage breast cancer incidence and mortality rates. However, disparities remain, indicating a need for continued monitoring and targeted interventions. The study highlights the importance of understanding and addressing geographic disparities in breast cancer outcomes. It underscores the role of screening and treatment in reducing disparities and the need for further research to identify and address remaining disparities. The findings suggest that while overall trends show improvement, disparities persist, and targeted efforts are necessary to achieve equitable outcomes.This study examines temporal trends in geographic disparities in small-area breast cancer incidence and mortality from 1988 to 2005. The researchers analyzed data from 200 counties using the Surveillance, Epidemiology, and End Results (SEER) Program to assess five breast cancer screening indicators: in situ breast cancer, stage I breast cancer, lymph-node positive breast cancer, locally advanced breast cancer, and breast cancer mortality. They used hierarchical Bayesian spatiotemporal methods to calculate absolute and relative geographic disparities and their changes over time. Results showed that for in situ breast cancer, absolute disparity increased by 93.7%, while relative disparity decreased by 61.5%. For stage I breast cancer, both absolute and relative disparity declined. Lymph-node positive breast cancer saw a 37.9% decline in absolute disparity and a 17.6% decline in relative disparity. Locally advanced breast cancer had a 66.5% decline in absolute disparity and a 17.8% decline in relative disparity. Breast cancer mortality also showed a 60.5% decline in absolute disparity and a 19.8% decline in relative disparity. The study concludes that geographic disparities in all breast cancer indicators except in situ breast cancer narrowed over time. Progress has been made in reducing geographic disparities in breast cancer outcomes, particularly in advanced-stage breast cancer incidence and mortality rates. However, disparities remain, indicating a need for continued monitoring and targeted interventions. The study highlights the importance of understanding and addressing geographic disparities in breast cancer outcomes. It underscores the role of screening and treatment in reducing disparities and the need for further research to identify and address remaining disparities. The findings suggest that while overall trends show improvement, disparities persist, and targeted efforts are necessary to achieve equitable outcomes.