Citation

Zlatkovic M. Mountain-Plains Consortium, North Dakota State University. Laramie, WY USA: Uni, 2022.

Copyright

(Copyright 2022, Mountain-Plains Consortium, North Dakota State University)

The full document is available online.

Abstract

Motorcycle riders and passengers are much more likely to be killed or severely injured in a crash, and on average, about 15% of all traffic fatalities include motorcyclists. The study uses 12 years of motorcycle crash data (2008–2019) from Wyoming, and eight years of data from Utah (2014–2021) and applies multinomial logistic and Bayesian multilevel regression modeling to determine the effects of various exposure measures on injury severity. Four models were developed and analyzed: (1) rural single motorcycle crashes; (2) rural multi-vehicle motorcycle-related crashes; (3) urban single motorcycle crashes; and (4) urban multi-vehicle motorcycle-related crashes. Overall, it was found that the most common factors affecting injury severity in motorcycle-related crashes include vehicle maneuver, driver action, junction relation, alcohol, animal and speed involvement, and helmet use. The vicinity of intersections significantly increases the odds of injury crashes in all urban and the rural multi- vehicle crashes, compared to no injury. Vehicle maneuvers, such as overtaking/passing, changing lanes, and negotiating a curve, are also associated with a more severe crash outcome. Helmet use was generally found to reduce fatal and serious injuries in crashes, with some exceptions, where other factors were more significant. Future work will include more detailed analysis on vehicle and person levels.