BACKGROUND Geographic disparities in access to trauma care may contribute to excess firearm-related mortality. Trauma system expansion has progressed unevenly across the United States, and national-level assessments of its implications for patient outcomes are lacking. STUDY DESIGN We conducted a nationwide, county-level cross-sectional epidemiological study of 446,584 firearm-related injuries from January 1, 2014, to December 31, 2023, using data from the Gun Violence Archive and the US Census Bureau. Each county's optimal transport time (ground or air) to the nearest Level I/II trauma center was calculated using geospatial modeling. The primary outcome was case fatality rate (CFR), defined as the proportion of deaths among all reported firearm injuries. Multivariable Poisson regression was used to evaluate the relationship between transport time and CFR, adjusting for county-level sociodemographic characteristics, urbanicity, and US Census region. RESULTS Of the 446,584 firearm injuries analyzed, 142,555 resulted in death (CFR, 31.9%). The population-weighted median optimal transport time was 30.9 minutes (interquartile range, 26.0–43.2). Case fatality rate increased significantly across transport time quartiles. After adjustment, each additional minute of transport time was independently associated with a 6.3% relative increase in CFR (incidence rate ratio 1.063; 95% confidence interval, 1.003–1.128; p = 0.04). CONCLUSION Prolonged transport time to trauma centers is significantly associated with increased firearm injury mortality across the United States, independent of sociodemographic factors. These findings support the use of geospatial information systems tools to guide trauma system planning, particularly in rural and underserved communities where geographic barriers remain a persistent threat to equitable outcomes. LEVEL OF EVIDENCE Epidemiologic Study; Level III.
Williams et al. (Mon,) studied this question.