Investigating the effect of drivers’ mental workload on the occurrence of driving anger among urban drivers in Qazvin city

One of the most important concerns of today's societies is the problem of road accidents and related deaths and injuries. Every year, road accidents can lead to many deaths and injuries, and the most important factor in the occurrence of these accidents is human factor. The role of human in accidents is assessed from different aspects, in which individual factors, including mental workload and anger, are among the most important predictors. Therefore, trying to investigate, prevent, and control of these factors in driving is one of the important issues; and for this reason, the present study examines the effect of mental workload on the occurrence of anger among drivers.

88 Qazvin city taxi drivers participated in this study. Driving Activity Load Index (DALI) and the Driving Anger Scale (DAS) were applied to measure mental workload and driving anger, respectively. In this study, first, the peak hours of traffic (11:00 to 14:00 local time) were selected based on the online traffic map of the city. Then, heavy traffic density routes were considered using Google Map. Based on high-traffic routes, a two-stage scenario was regarded to measure the mentioned scales. The measurement of the studied scales was done by completing the questionnaire in the middle and at the end of the route. To analyze the collected data, paired t-test and correlation and regression analyses were employed.

The results of the study showed that long driving and traffic environment can greatly affect all dimensions of mental workload (P <0.001). Mental workload had a great impact on increasing driving anger (P <0.001).                                

The results of this study showed that increases in drivers' mental workload can lead to increased levels of driving anger, which indicates the influence of traffic environment on driving behavior; therefore, measures and suggestions are required to prevent driving anger in order to improve drivers’ activities and prevent accidents.