A new study finds that driving while distracted can more than double your risk of an accident for more than half of your trips. Researchers from the Virginia Tech Transportation Institute found that being in an emotional state while driving increases the risk of accidents, as do reaching for a handheld cell phone, reading, writing, reaching for another object, and using touchscreen menus on a vehicle instrument panel.
A Virginia Tech press release about the study said the findings were important because younger population of drivers, particularly teens, are more likely to engage in distracting activities while driving. Tom Dingus, lead author of the study and director of the Virginia Tech Transportation Institute, said:
Our analysis shows that, if we take no steps in the near future to limit the number of distracting activities in a vehicle, those who represent the next generation of drivers will only continue to be at greater risk of a crash.
Joshua A. Krisch, writing for Vocative, said that about 3,000 people are killed annually in the United States as a result of distracted driving. And in 2012 alone, almost 500,000 people were injured in distracted driving crashes.
The Virginia Tech researchers based their findings on an analysis of the Second Strategic Highway Research Program Naturalistic Driving Study — the largest study ever made of light vehicles in a naturalistic setting. The study involved more than 3,500 participants and six data collection sites in the U.S.
The database available to researchers had information on more than 1,600 verified crashes that ranged in severity from low (such as hitting the curb) to high (such as crashes reported by police). Researchers considered 905 high severity crashes that involved injury or property damage. They found that 90% of those crashes involved driver-related factors including drowsiness, error, impairment, and distraction.
The findings reveal the biggest accident risks faced by drivers. This is the first time a study has definitively determined the extent to which driver-related factors result in crashes, Dingus said.
Emotional Agitation
Researchers found that driving while visibly angry, sad, crying, or otherwise emotionally agitated can increase accident risk by almost 10 times. Driving well over the speed limit (although “well over” is not defined) can increase accident risk by 13 times. The risk of accidents is also increased when a driver makes performance errors, such as sudden or improper braking, and being unfamiliar with a road or a vehicle.
In a surprising result, the study found that driving behaviors previously thought to increase accident risk, including applying makeup or following the vehicle in front too closely (also known as tailgating) were not very prevalent in the accident data, or were not present at all in crashes the team analyzed. In addition, interacting with a child in the back seat was found to have a risk lower than the base risk value, an effect the study calls “protective.”
Defining and Mitigating Driver Risk
The study, which appears in this week’s Proceedings of the National Academy of Sciences, aims to help policymakers, educators, drivers, law enforcement officials, and vehicle designers “to define and help mitigate” driver risks, Dingus said.
To conduct the study, researchers placed cameras, sensors and radar in volunteer participants’ vehicles, in an unobtrusive way. The equipment continuously collected real-world driver performance and behavior data, during the whole time that volunteers were driving their vehicles. Each distracted driving behavior was compared with ideal driving behavior, defined as that of a person who is alert, attentive, and sober.
Each driver participated in the study for a period between one and two years, in what became a grand total of 35 million miles of data. This is one of the largest projects ever funded by the National Academy of Sciences. Virginia Tech Transportation Institute, one of several partners, was funded with more than $50 million.
Frisch ends his article by exhorting drivers to only drive when sober, stay off cell phones, avoid fiddling with the A/C too much, and wait until arriving at their destinations before eating.