*The following is excerpted from an online article posted on HealthDay.
Nearly 40 percent of teen drivers in the United States say they text while driving, a new survey finds.
Researchers analyzed survey data from teen drivers aged 14 and older in 35 states and found that more than a third said they'd texted while driving at least once in the month before the survey. In 34 of the 35 states, text messaging by drivers under the age of 21 is illegal.
Rates of teen texting while driving ranged from 64 percent in South Dakota to 26 percent in Maryland. Teens were also more likely to text and drive in states that had a lower minimum learner's permit age and in states with higher percentages of student drivers.
Five states where more than 50 percent of teen drivers said they texted while driving had a learner's permit age of 15 years or younger, the researchers noted.
"The increase in texting while driving at the age when teens can legally begin unsupervised driving was not surprising," said the lead author, Dr. Motao Zhu. He is principal investigator at the Center for Injury Research and Policy at Nationwide Children's Hospital, in Columbus, Ohio.
"Graduated driver licensing laws could have an impact on texting while driving behavior: the earlier teens start driving, the earlier they start texting while driving," Zhu added in a hospital news release.
The investigators also found that teens who engage in other risky driving behaviors were also more likely to text while driving. Those who didn't regularly wear seat belts were 21 percent more likely to text while driving than frequent seat belt users. Those who admitted to drinking and driving were nearly two times more likely to text while driving than those who did not drink and drive.
The researchers also pointed out that the survey findings likely underestimate teen drivers' cellphone use. Because the survey only asked about "texting and e-mailing while driving," it may not take into account the many ways teens use their cellphones while driving, such as answering or placing a phone call, checking social media, selecting music and accessing other apps.
The study was published in the Journal of Adolescent Health.