Calm down, please!: Exploring the effects of driving anger expression (DAX) on traffic locus of control (T-LOC) and crash involvement among drivers in Tehran, Iran

Since driving anger expression and its adverse consequences is an issue that has not been resolved over the last years or even has increased among Iranian drivers over time, this study aimed to evaluate the driving anger expression (DAX) and its impacts on the traffic locus of control (T-LOC) and crash involvement among drivers in Tehran, Iran. By collecting data from 1035 participants, exploratory factor analysis identified significant constructs of DAX including "Adaptive, "Verbal anger expression", "Use of the vehicle to express anger", and "Personal physical anger expression" and T-LOC including "Self", "Other drivers", "Vehicle/environment", and "Fate/luck". A two-phase approach of K-means clustering and a logistic regression model was then used to eval-uate the effects of driving anger expression on T-LOC and crash involvement. The results revealed that while males and younger drivers reported more aggressive orientation in driving anger sit-uations, females, older drivers, and those with higher driving experience significantly showed a higher level of adaptive orientation in driving anger situations. The logistic regression models showed that external T-LOC (believing that other people and factors are responsible for an ac-cident, not themselves) was significantly higher in middle-aged drivers and those with 11-20 years of driving experience. Also, drivers with adaptive anger expression were less likely to report a high level of external T-LOC. On the other hand, the use of the vehicle to express anger increased the probability of external T-LOC. According to the results, using the vehicle to express anger can significantly increase the probability of crash involvement among drivers.