Nonetheless, very little seems to be known about why certain drivers get so angry, and how infuriated drivers impact the mental health of others.

Reginald Smart, Ph.D., a senior scientist at the Center for Addiction and Mental Health in Toronto, Canada, and his colleagues published the results of a study on these issues in the November Canadian Journal of Psychiatry.

They found that there seem to be five categories of drivers—from those who almost never engage in road rage and who are almost never affected by it to hard-core road-rage perpetrators who are also often road-rage victims.

Smart and his coworkers based their study on a phone survey of some 2,600 individuals who were representative of Ontario adults aged 18 and older. The subjects were asked about different types of driving behavior in which they had engaged during the previous year, about other people’s driving behavior during the previous year that had impacted them, and they were asked questions taken from the General Health Questionnaire. The General Health Questionnaire is a widely used scale for detecting nonpsychotic psychiatric illness and capturing psychological distress, anxiety, and social functioning. Smart and his team then analyzed the survey data to get some idea of how widespread road-rage perpetration and victimization are; what types of people engage in road rage; what types of people are its victims; how the mental health of road-rage perpetrators compares with that of road rage victims; and how the mental health of both compare with that of persons who are neither perpetrators or victims. The researchers then used their results to classify 2,442 of the subjects into five groups.

The largest group (1,188 subjects) had engaged in little or no road rage and also had had little or no contact with road-rage perpetrators. The majority were female, their average age was 46, and of all five groups, they scored the lowest on current psychiatric distress.

The second-largest group (612 subjects) had had the experience of being shouted at while driving, but had engaged in little road-rage behavior themselves. They scored a little higher on psychiatric distress than the first group did.

The third-largest group (336 subjects) had been shouted at while driving more than had members of the above group. But they themselves had also done a lot of shouting while driving. They scored a little lower on psychiatric distress than the second group, but a little more than the first group did.

The fourth-largest group (237 subjects) had done a lot of shouting while driving. However, they hadn’t engaged to any great degree in other road-rage behaviors such as threatening to hurt another person, trying to damage another person’s car, or attempting to hurt another person. Nor had they had much experience with road-rage victimization. They were more likely than members of the above groups to be male and younger (average age was 38). Their psychiatric distress scores were about the average for all five groups.

Finally, the smallest group (69 subjects) turned out to be hard-core road-rage perpetrators. They were the only group to have engaged to any notable degree during the previous year in the most serious forms of road rage—attempting to damage another person’s car or attempting to hurt another. They also scored the highest of all five groups on current psychiatric distress. But probably the most surprising discovery about this group is that they had not only engaged in dangerous road-rage behaviors, but had often been victims of road-rage themselves. Or as David Goldbloom, M.D., a senior medical advisor at the Center for Addiction and Mental Health as well as a professor of psychiatry at the University of Toronto, told Psychiatric News: "This finding suggests the possibility of self-perpetuating cyclicity."

In all, Goldbloom added, "the authors of this study have brought a level of conceptual sophistication and statistical analysis to a social problem that has already been ‘iconified’ in popular movies. What they show is that road rage is actually a complex construct with, in some cases, a linkage to psychiatric disorder....This study should also go some way to dissipating American stereotypes of Canadians as simply and perpetually ‘nice’; clearly, Canadian roads provide a venue for the expression of affect."

The study was financed by the Center for Addiction and Mental Health and the Networks of Centers of Excellence.

The study, "Psychiatric Distress Among Road Rage Victims and Perpetrators," is posted online at www.cpa-apc.org/Publications/CJP/current/smart.asp. ▪