Certain Personalities Make Some Professional Truck Drivers More Dangerous than Others

When you get behind the wheel, are you more worried about your own driving abilities or those of other drivers on the road? Although traffic accidents involving large trucks in particular occur relatively infrequently, their consequences are alarming. In the United States alone, accidents involving commercial trucks result in 4,000 deaths per year and over 100,000 injuries. And these accidents don’t result just in physical harm—they take a toll on the wallet as well. The average cost of an accident involving commercial trucks is $91,000, which balloons to $3.6 million for fatal accidents.

So what’s standing between you and a devastating encounter with a semi-truck? Not surprisingly, human factors such as driver error, distraction, carelessness, and aggressive driving are the primary cause of over 90% of automobile fatalities. But often, something about the driver led them to engage in behaviors that increase the chances of an accident, such as drinking on the job, driving while sleepy, or texting while driving. So, for commercial truck drivers, their personality and its effects on their decisions and behaviors could potentially be the difference between an uneventful day at work and becoming another crash statistic.

Research has shown that the human personality is organized around five primary characteristics: Extraversion, Agreeableness, Conscientiousness, Neuroticism, and Openness to Experience. But within each of these broad dimensions are a number of more specific attributes called “facets” that differ in subtle but important ways. For instance, the broad trait of conscientiousness includes specific facets such as impulse control, reliability, and orderliness, among others.

Although research documents general associations between broad personality traits and automobile accidents, the goal of our study was to go beyond broad traits to explore how specific facets of personality might contribute to truck drivers’ likelihood of having an accident. To do so, we studied drivers who worked for six commercial trucking firms who completed a personality measure that assessed 41 facets of personality as part of their hiring process and whose employers kept records of their accidents.

Overall, certain personality facets within the traits of Extraversion, Conscientiousness, Neuroticism, and Openness to Experience showed significant relationships with accidents. Drivers who showed a greater tendency to show off, to act without considering risks or consequences, to think creatively or “outside the box,” and a propensity to react with anger, anxiety, guilt, or lack of empathy were more likely to have accidents.  However, none of the facets associated with the trait of Agreeableness were related to accidents.

The logic behind some of these relationships are obvious. For instance, the combination of trying to show off or being prone to anger while controlling a 40-ton truck is clearly destined for mishap of some kind. Others, though, are less clear. For example, a propensity towards anxiety could lead drivers to hesitate or freeze up under pressure, which may lead to poor decisions or delayed reactions. A lack of empathy—the ability to put oneself in another’s place—may also contribute to behavior that endangers other drivers. And although creativity is highly valued in many professions, truck drivers who operate outside the norm may be more likely to contribute to accidents.

These findings involving facet-level personality characteristics reveal much more about which truck drivers are likely to be in an accident than broad, general traits such as Conscientiousness. Thus, they might be usefully applied to improve selection and training procedures at commercial trucking firms as well as in other high-risk occupations such as construction. If a well-designed personality assessment can point us toward employees who have a lower probability of being in an accident, firms could potentially lower the physical and financial harm caused by accidents each year. Given the high stakes, this seems like a small price to pay.

For Further Reading

Landay, K., Wood, D., Harms, P. D., Ferrell, B., & Nambisan, S. (2020). Relationships between personality traits and automobile accidents among truck drivers. Journal of Research in Personality, 84, 1-10. https://doi.org/10.1016/j.jrp.2019.103889

Karen Landay is a Ph.D. student at the University of Alabama.

P. D. Harms is an Associate Professor of Management and the Morrissette Faculty Fellow in Leadership and Ethics at the University of Alabama.