(Reuters Health) - Teen drivers who wisely stow away their cell phones while they’re behind the wheel still need to be aware of another important risk factor for accidents, a small study suggests.

Even when not distracted by their phones, adolescents who reach for or handle other objects while driving are almost seven times more likely to crash than teens who don’t reach for anything at all, the study found.

“Compared to older drivers, teens’ limited driving experience and youthful characteristics may contribute to their higher risk for distraction when engaging in secondary tasks while driving,” said lead study author Pnina Gershon of the National Institutes of Health in Bethesda, Maryland.

“Furthermore, teens tend to overestimate their ability to multitask while driving and are considered to be early adopters of technology, meaning that they are more likely to embrace new technologies and possibly use them while driving,” Gershon said by email.

Motor vehicle crashes are the leading cause of death and disability among drivers ages 15 to 20, researchers note in the American Journal of Preventive Medicine.

And teens who manually operate cellphones while driving are almost three times more likely to crash than young drivers who don’t. But while researchers have long understood that distracted driving plays a big role in this risk, the current study offers fresh evidence that the chances of a crash can vary based on the type of activity that causes teens to take their attention off the road.

In the current study, researchers outfitted cars used by 82 newly licensed teen drivers with cameras and sensors to detect how various distractions and situations might contribute to inattention or crashes. The teens drove these cars during their first year on the road, starting when they were 16.5 years old on average.

When the researchers compared video clips taken during accidents to clips from random periods of driving, they found teen drivers engaged in at least one other task while driving in 51 percent of crashes, and about 56 percent of the time when they didn’t get in a collision.

Interactions with passengers in the car happened 21 percent of the time whether or not teens crashed the car.

Manual use of cell phones, as opposed to hands-free operation, occurred in 10 percent of crashes but just 5 percent of the time when teens didn’t have a collision.

Reaching for snacks, drinks or other objects happened in 11 percent of crashes compared with just 3 percent of the time when these young drivers didn’t have a collision.

Looking away from the road too long accounted for 41 percent of the crash risk associated with cell phone use, while handling other objects explained 10 percent of the risk.

The study wasn’t a controlled experiment designed to prove whether or how cell phone use or handling other objects might directly cause crashes. It also wasn’t designed to determine how much safer teens might be with hands-free phone use than with manual cell phone operation.

Even so, technology may be especially distracting for younger and less experienced drivers, said Dr. Scott Hadland, a pediatrician and adolescent specialist at Boston Medical Center who wasn’t involved in the study.

“Experienced drivers are likely better able to compensate for poorer driving while they are distracted than inexperienced drivers,” Hadland said by email. “It’s also possible that experienced drivers are more able to mitigate the risk of distracted driving by, for example, choosing to use their cell phones at lower risk times such as when driving slowly or when there are few other drivers around.”

When it comes to road safety, parents need to lead by example, said Despina Stavrinos, director of the Translational Research for Injury Prevention Laboratory at the University of Alabama at Birmingham.

“Parents should set a positive example by limiting cell phone use while driving so that their kids can learn what is appropriate and safe driving behavior,” Stavrinos, who wasn’t involved in the study, said by email.

SOURCE: bit.ly/2TF8PUE American Journal of Preventive Medicine, online February 21, 2019.