Amber DeJohn, Ph.D., Assistant Professor in the Department of Geography at Florida State University, has received a sub-award through the National Institutes of Health to develop national measures of healthcare accessibility. These data could help researchers better understand risk factors for Alzheimer’s Disease and Related Dementias (ADRD).
The project, “National, Multidimensional Measures of Healthcare Accessibility for ADRD Risk Factors,” is funded through an NIH U24 award administered by the Gateway Exposome Coordinating Center (GECC). Dr. DeJohn’s sub-award totals $60,000, with work running from August 2025 through July 2026.
Dr. DeJohn serves as principal investigator (PI) and is collaborating with co-PI Kyusik Kim, Ph.D., Assistant Professor of Geography and Anthropology at Kennesaw State University and an FSU Geography alumnus. Together, the team will compute accessibility scores for the entire United States, calculating how easily residents can reach primary care physicians, hospitals, optometrists, pharmacies, and other key health services. DeJohn conceptualized the grant, coordinates the team’s collaboration with GECC, and oversees the research process to ensure the project meets its goals.
“We are compiling several measures of spatial accessibility to health care services,” Dr. DeJohn said. “This might include a measure like: how many primary care doctors are within a 15-minute drive of your home? These data are intended to support public health researchers who are tackling risk factors for Alzheimer’s Disease and Related Dementias.”
“I’m excited to incorporate new data sources to improve our understanding of health care service utilization,” Dr. DeJohn said. “We have also conducted work evaluating the quality of input datasets commonly used in these analyses, which gives me confidence in the robustness of our final product.”
A distinctive feature of the project is its “multiverse” approach. Rather than relying on a single accessibility index, the team will compute and compare several existing and novel measures. This method helps surface the consistent signal across approaches, providing researchers with a more transparent understanding of how geography shapes healthcare access.
Dr. DeJohn anticipates that the work will continue after the grant is completed. The team intends to apply for additional funding to build on the foundation established through this project.
Amber DeJohn is an Associate with FSU’s Spatial Data Science Center and the Pepper Institute on Aging and Public Policy.
For more information about the Department of Geography, click here.
For more information about the Gateway Exposome Coordinating Center, click here.