Analyzing teen drivers' exposure to crash risk: An activity space-based approach

Teen drivers' exposure to crash risk depends on where and how much they drive. Of the few published studies examining driving patterns and crash exposure, none focused on teen drivers, the highest crash risk group of all ages. This study used activity space measures to analyze everyday driving activities, resultant crash exposure, and associated factors for teen drivers aged 16-17. Using driving-related GPS-trajectory data collected from 76 teens for one month, we used a network-based activity space measure to categorize teens into three groups. We estimated each teen's crash exposure by analyzing their travel frequency on specific roads and crash density on those roads for the broader young population. Lastly, we applied a cumulative link mixed model to assess the influence of demographic, road, and urban-social environmental characteristics on crash exposure and their variations across three driving activity-based teen groups. Our findings revealed that the geographic extent of teens' everyday driving, measured through their activity space, varied extensively, resulting in varying crash exposure levels among them. The results suggested that teens' exposure to crashes was associated with both the extent of their driving activity space and the road and urban environments in which they drive. Teens, who mostly drove within smaller geographic spaces experienced greater crash exposure while driving on primary roads and in poor neighborhoods compared to those driving extensively but mostly on highways. These findings have implications for urban planning and policymaking, identifying urban environments, particularly those crash-prone for teen drivers, and informing strategies to mitigate crash risks.