Understanding motorcycle crash involvement: Insights from regular motorcyclists and food delivery riders in Vietnam.

Motorcycles have become a primary mode of transportation in many low- and middle-income countries, including Vietnam, where they are widely used for personal transport and commercial activities. The growing reliance on motorcycles, driven by rapid urbanization and the rise of app-based delivery platforms, has brought economic benefits but also significant public health concerns due to the high incidence of road traffic crashes. This study, based on a questionnaire survey targeting regular motorcyclists and food delivery riders in Vietnam, examines and compares the factors contributing to crash involvement between two groups, regular and delivery riders. Random parameters models with heterogeneity in means and variances were employed to capture variability in respondent behaviors. The results reveal that psychological factors, such as negative attitudes toward traffic rules and intentions to violate rules, significantly increase crash involvement for both regular and delivery riders, with the effect being more pronounced among delivery riders due to job pressures. Conversely, positive attitudes reduce crash involvement but are less effective for delivery riders due to high time pressures and frequent distractions. Perceived severity of crashes and the swiftness of sanctions also play critical roles: higher perceived severity promotes safer behavior, while the threat of sanctions deters risky actions for both groups. Rider attributes, such as age, education, and income, influence crash involvement, with younger and lower-educated riders facing higher risks among both groups due to inexperience and limited traffic knowledge, while income effects vary between regular and delivery riders. Travel characteristics, such as travel durations of more than two hours, increase crash involvement due to fatigue and exposure, particularly affecting delivery riders who navigate complex urban environments and face frequent distractions. The findings also highlight the importance of addressing heterogeneity in data analysis for more comprehensive insights. Moreover, based on these results, various policy implications are provided to reduce traffic crashes and enhance safety for motorcyclists in motorcycle-dominated countries.