Linking built environments and pre-crash pedestrian behaviors: A Safe Systems approach to crash severity

OBJECTIVE: Pedestrians are the most vulnerable road users, and the number of crashes has increased in the past decade. Within the Safe Systems framework that recently gained attention, crashes result from the interaction between environmental factors and the parties involved, and pedestrian safety can be improved by creating more supportive environments. Previous studies have examined the influence of built environment and other risk factors on crash severity, yet little is known about how their protective effects differ across pre-crash pedestrian behaviors. METHODS: = 17,233), our analysis contributes to this literature by discerning the role of built environment across different situational contexts, categorized by three pedestrian behaviors at the time of crash: crossing at crosswalk, crossing not at crosswalk, and walking along traffic. Multinomial logit models are separately estimated for each case. RESULTS: Across all crashes, those involving pedestrians aged over 65 years, large vehicles, unlit road conditions, and high speed limits are more likely to result in severe pedestrian injuries. Behavior-specific models show that even when pedestrians are crossing mid-block, higher pedestrian-oriented network density mitigates injury severity. Additionally, crashes are more likely to be severe in areas with dense auto-oriented links, particularly when pedestrians are walking along the traffic, often due to lack of supportive infrastructures. Lastly, where pedestrians are at crosswalks, drivers aged 20-24 years are associated with a higher likelihood of serious pedestrian injuries. CONCLUSIONS: These findings highlight the heterogeneous role of built environments in shaping crash outcomes depending on contexts. The patterns align with the Safe Systems framework such that insufficient built environments elevate injury severity, while pedestrian-oriented infrastructures can mitigate harm even when behaviors are less predictable. Thus, infrastructure improvements should be recognized as behavioral interventions and injury prevention strategies that absorb human errors, not simply as street environment upgrades.