Age-Based Stratification of Drivers to Evaluate the Effects of Age on Crash Involvement

:Traffic crashes imperil roadway users and impose a considerable economic burden on society. Previous studies have investigated several aspects of traffic crashes such as severity, frequency, and influential factors, yet the causal and spatial differences between crashes involving drivers from different age groups remain unclear. In this paper, we illustrate the causal, spatial and temporal variations in crash involvement patterns of different age groups, including age 16-49, 50-64, and 65+. Furthermore, we stratified the aging drivers (65+) in order to explore the age-specific differences within this group, considering that the changes brought by aging may differ tremendously at different stages. For this purpose, we implemented an approach with two distinct phases: (a) a geographic information system (GIS)-based spatiotemporal analysis, and (b) a multinomial logistic regression analysis. Results indicate that crashes of different age groups differ not only in terms of influential factors but also spatially and temporally on the roadway network. The findings of this study will be eminently useful for public and/or private agencies to identify and address problematic issues particularly for aging drivers, and thus will enhance the safety and mobility of aging roadway users as well as entire population.