DANVILLE - Teen drivers diagnosed with attention-deficit/hyperactivity disorder (ADHD) were found to have more variability in their speed and tended to veer out of their lane more frequently than teens without ADHD and texting just made their performance worse. These findings were recorded as part of a new study led by Megan Narad, M.A., a Geisinger Medical Center clinical psychology resident.
She and seven other researchers from the Center for ADHD at Cincinnati Children's Hospital Medical Center studied the performances of 61 new teen drivers (28 with ADHD, 33 without) during 40-minute tests on a driving simulator under three conditions - no distraction, cellphone conversation and texting. Their study was published in the Aug. 12 edition of JAMA Pediatrics.
Their study is the first to assess the combined effects of ADHD, driving inexperience and cell phone distraction/texting among teen drivers.
"There are some studies on texting and driving, others on ADHD and driving, and some on even novice driving, but there's not one that looks at all three of those driving risk factors," said Narad, who conducted the research for her doctoral dissertation at the University of Cincinnati.
Prior to their simulations, a much larger proportion of ADHD subjects reported receiving at least one traffic violation (17 percent) compared with the non-ADHD subjects (6 percent). The researchers chose to test ADHD subjects without medication to more accurately evaluate their ADHD-related deficits.
The effects of cellphone distraction were found to be large and evident for all subjects, resulting in changes in average speed, speed variability and variability of lane position. Texting was the most impairing distraction to all subjects, and particularly compounded the negative performance of ADHD drivers.
"It makes it even worse. They're starting off at a deficit (because of the ADHD), so they're more distracted already, and then we're adding this other distraction (texting) into their driving performance," said Narad. "It's this kind of additive problem that is even scarier than a typical 16- or 17-year-old who is driving."
The authors wrote that their study highlights the need for education and enforcement of regulations against texting for drivers from this age group.
"I don't think any teenager or novice driver should have the distraction of a phone, whether it's being used for texting, email, or whatever it is," Narad said. "This study was alarming to be a part of, seeing how these kids, who aren't experienced drivers yet, were distracted by cellphone use. It may not be a big deal in a simulator, but it's a big deal out on the road."
The researchers also recorded the eye gazes of the subjects during their driving simulations under the three conditions and they're analyzing those findings for a future study.