E-Scooter and Bicycle Healthcare Utilization in U.S. Emergency Departments: Examined Through Mode-Specific Diagnostic Codes.

Few national comparisons exist on healthcare utilization among e-scooter users, and prior research was limited by the absence of e-scooter-specific ICD-10-CM codes before 2021. Using newly implemented codes, this cross-sectional study compared emergency department disposition and injury patterns between e-scooter riders and bicyclists using the 2021 Nationwide Emergency Department Sample (n = 239,457 weighted encounters). Multivariable logistic regression adjusted for demographic, geographic, and temporal confounders, with interaction terms for insurance status, substance use, and motor vehicle involvement. E-scooter riders were more often female (46.5% vs. 24.7%) and under age 18 (47.6% vs. 37.4%) than bicyclists. Overall adjusted odds of admission or transfer did not differ significantly between groups (OR = 1.03; 95% CI: 0.86-1.23). Motor vehicle involvement significantly modified this relationship, with e-scooter riders showing higher odds of admission (OR = 1.67; 95% CI: 1.12-2.48). No significant effect modification was detected for insurance status or substance use. E-scooter riders more frequently sustained distal extremity fractures consistent with low-energy falls, while bicyclists experienced more proximal fractures and internal trauma. Updated ICD-10-CM codes improve e-scooter injury surveillance, and motor vehicle involvement represents a priority target for mode-specific prevention and infrastructure investment.