Driving anger reduces the evasive response likelihood in near-crash events: Insights from SHRP 2 Naturalistic Driving Study.

INTRODUCTION: Anger is a prevalent emotion that has been shown to negatively impact driving behavior, contributing to aggressive driving and road rage-both of which are well-known threats to traffic safety. This study investigated the effects of driving anger on evasive maneuvers immediately preceding crashes and near-crashes using naturalistic driving data, with particular attention to how emotional state interacts with event severity. METHODS: This study used data from the Second Strategic Highway Research Program (SHRP 2) Naturalistic Driving Study (NDS) and employed a case-cohort approach to evaluate the influence of anger on drivers' reactions to traffic conflicts. Association analyses were performed to evaluate the relationship between driving anger and other risk factors, including driver age, gender, and risky driving behavior scores. Logistic regression models were constructed to investigate the likelihood of an evasive maneuver given driver age, event severity, and the presence of driving anger. RESULTS: Findings showed that teen drivers (ages 16-19) and young drivers (ages 20-29) were more likely to take evasive maneuvers in response to safety-critical events (i.e., near-crash and crash events) compared to middle-aged drivers. There was an interaction between event severity and driving anger presence; angry drivers were less likely to perform evasive maneuvers in near-crash events compared to non-impaired drivers. Among events with evasive maneuver present, anger was associated with comparable likelihood of braking, but reduced likelihood of combined braking-and-steering maneuvers compared to no impairment. CONCLUSIONS: The findings demonstrate that driving anger alters both the likelihood and structure of evasive responses in safety-critical situations, particularly in less severe but time-sensitive conflicts. PRACTICAL APPLICATIONS: Our findings can inform the design of in-vehicle driver monitoring and alert systems and active safety technologies aimed at mitigating the risk of "no avoidance maneuver" behavior under heightened emotional states.