Background: Many rural, low-income, and historically underrepresented minority communities lack access to trauma center services, including surgical care and injury prevention efforts. Along with features of the built and social environment at injury incident locations, geographic barriers to trauma center services may contribute to injury disparities. This study sought to classify injury event locations based on features of the built and social environment at the injury scene, and to examine patterns in individual patient demographics, injury characteristics, and mortality by location class.

Methods: Data from the 2015 Maryland Adult Trauma Registry and associated prehospital records (n = 16,082) were used in a latent class analysis of characteristics of injury event locations, including trauma center distance, trauma center characteristics, land use, community-level per capita income, and community-level median age. Mortality effects of location class were estimated with logistic regression, with and without adjustment for individual patient demographics and injury characteristics.

Results: Eight classes were identified: rural, exurban, young suburban, aging suburban, inner suburban, urban fringe, high-income urban core, and low-income urban core. Patient characteristics and odds of death varied across classes. Compared with inner suburban locations, adjusted odds of death were highest at rural (odds ratio [OR], 1.98; 95% confidence interval [CI], 1.36-2.88), young suburb (OR, 1.57; 95% CI, 1.14-2.17), aging suburb (OR, 1.36; 95% CI, 1.04-1.78), and low-income urban core (OR, 1.38; 95% CI, 1.04-1.83) locations.

Conclusion: Injury incident locations can be categorized into distinguishable classes with varying mortality risk. Identification of location classes may be useful for targeted primary prevention and treatment interventions, both by identifying geographic areas with the highest risk of injury mortality and by identifying patterns of individual risk within location classes.

Level of evidence: Prognostic and epidemiological, level III.