Aggressive drivers pose a risk to road safety, and researchers have quantified the difference.
Researchers at the University of Warwick in the UK conducted the first systematic analysis of more than 30 global studies of aggressive driving, a behaviour they defined as: “intentionally endangering others physiologically, physically or both.”
Their study published in Accident Analysis and Prevention is the first to quantify road rage.
Aggressive driving behaviours might include speeding, running red lights, weaving in and out of traffic, and rapidly accelerating and decelerating.
According to the paper, aggressive drivers went on average 5.32 km/h faster than normal drivers.
Those drivers also made significantly more mistakes – things like collisions, ignoring stop signs, exceeding speed limits and crossing lane markers. When drivers are in an aggressive state they made on average 2.51 more errors than a normal driver, the study says.
It is likely that both factors – speed and mistakes – contribute to road traffic injury, one of the leading causes of death globally. The World Health Organisation says road accidents killed around 1.28 million people in 2019.
Aggressive driving – which some call ‘car brain’ – is relatively widespread. The study cites research suggesting 78% of US drivers engaged in at least one aggressive driving behaviour in the past year. And the behaviour has knock-on effects, usually inducing aggressive driving in others.
The researchers suggest one explanation for aggressive driving might be the ‘frustration-aggression theory’. When drivers are frustrated by factors like traffic congestion, some choose an aggressive response. They hypothesise the higher rate of mistakes could be due to drivers diverting cognitive resources away from driving, to expressing anger.
Lead author of the study Zhizhuo Su says: “…this research is significant because, as the era of autonomous vehicles approaches, road traffic will be a mix of both autonomous and non-autonomous vehicles, driven by people that may engaged in aggressive driving.
“This is the first study to characterise aggressive driving behaviour quantitatively in a systematic way, which may help the autonomous vehicles identify potential aggressive driving in the surrounding environment.”