HealthDay News — Texting while driving is associated with negative outcomes for all teen drivers, but particularly those with ADHD, study findings indicate.
Sending a text message during a diving simulation doubled the risk of weaving into oncoming traffic in all teen drivers, but the effect on variations in speed and weaving were even greater in teens with ADHD, Jeffrey N. Epstein, PhD, of the Cincinnati Children’s Hospital Medical Center and colleagues reported in JAMA Pediatrics.
ADHD was associated with poorer performance overall on pooled average speed and variability in speed and lateral position within a two-lane street driving simulation (P=0.01).
During texting, teens with ADHD strayed outside of their lane for 3.30% of the drive compared with 1.76% of the time when driving without the distraction, which translated to a 371% increase in time spent outside their lane compared with undistracted controls, the researchers found.
For teens without ADHD, texting appeared to be equivalent to having the disorder, bringing the time spent outside their lane to 2.03% compared with 0.70% when driving without distraction.
“The compounded effects of ADHD on immaturity and driving inexperience in teens likely result in higher ADHD-related crash risk in teens,” the researchers wrote.
The study involved 61 newly licensed teenagers aged 16- to 17-years-old, 28 of whom had ADHD. The teens were given cell phones with a hands-free headset and participated in a simulated drive — during which one unexpected event, such as another car suddenly merging into the driver’s lane — occurred. The simulation was completed under three conditions: no distraction, a telephone call and texting.
Compared with controls, participants with ADHD reported fewer months of driving experience and a higher proportion of driving violations.
Overall, texting was associated with slower driving and more variability in speed and lateral position compared with no distraction or with a phone conversation (both all P<0.001).
“While slower speeds may be beneficial in some driving situations, reductions in speed, particularly if occurring irregularly, can impact traffic congestion and highway safety,” the researchers wrote.
Adolescents with ADHD demonstrated more variability in speed and lane position than control subjects, when controlling for months of driving history, the researchers found.
Among participants with ADHD, standard deviation in miles per hour was 9.71 to 11.01 across the three driving conditions compared with 7.96 to 9.62 among non-ADHD kids. The standard deviation for lateral position in the lane was 1.24 to 1.85 ft versus 0.95 to 1.51 ft, respectively. Braking reaction time was not different between the groups.
“In conclusion, this study clearly demonstrates that both an ADHD diagnosis and texting while driving present serious risks to the driving performance of adolescents,” the researchers concluded. “There is a clear need for policy and/or intervention efforts to address these risks.”