Distracted teenagers are a lot more dangerous than previously thought.

A recent University of Iowa study of 1,700 in-car videos found some type of distraction — such as texting or a passenger — causes about 60 percent of all teen crashes.

The study was the first of its kind, said Cher Carney, a senior research associate at the Iowa Public Policy Center and one of the researchers who conducted the study.

Previous data, relying on police reports, showed only 14 percent of all crashes were distraction related.

“A lot of times people are unwilling for various reasons to tell police they were on their phone, or may not even realize they were distracted,” she said.

According to the research, interacting with other passengers caused 15 percent of crashes. The next highest rate was 12 percent of crashes from phone use.

The AAA Foundation for Traffic Safety funded the study.

“We’ve always felt distracted driving, especially among teens, has been underreported,” said Gail Weinholzer, the director of public affairs for AAA Minnesota and Iowa. “[The study] now allows us the opportunity to give further education and work toward getting people to understand the seriousness of the issue.”

In addition, Weinholzer said, she believes there needs to be a tightening of legislation surrounding graduated driver’s licenses in Iowa.

In most states, before getting their full licenses, young drivers are limited to one minor passenger who is not a relative, and in some states, they aren’t allowed any passengers at all.

Although Iowa has a passenger restriction on graduated driver’s licenses, it’s the only state in the United States that allows parents to sign a waiver to opt their child out of the restriction.

With the waiver active, Iowa joins four other states in the county — South Dakota, North Dakota, Mississippi, and Florida — that have put no passenger restrictions on learning drivers.

“What we’ve found in our research is, as the number of passengers a teen has in the car increases, the number of distractions increase,” Carney said.

A report released in 2013 found 15- to 17-year-old drivers were eight times as likely to be in a fatal accident when there were two or more teen passengers.

“[AAA doesn’t] want any teens in the vehicle for the first six months of driving and prohibits cell-phone use of any type until the age of 18,” Weinholzer said.

Currently in Iowa, using a phone and driving without a full license is a primary offense, meaning teens can be pulled over for nothing other than texting.

For adults in Iowa, however, using a phone is a secondary offense, meaning the driver cannot be pulled over for cell-phone use alone.

A bill that recently cleared the Iowa Senate, however, aims to make texting while driving a primary offense for all drivers. Weinholzer said she believes in addition to tightening graduated driver’s license laws, such legislation would help reduce the number of crashes.

Kara Macek, the communications director for the Governors Highway Safety Association, which represents all U.S. highway safety offices, said many aspects of Iowa’s licensing laws are troubling, including the lack of passenger restrictions.

“In Iowa, you can begin to drive as early as age 14,” she said. “There’s only a handful of states that start that young, and we recommend 16.”

Macek also said Iowa has very loose nighttime driving restrictions, allowing learners to drive as late as 12:30 a.m. The best practice they recommend would have the restriction start around 10 p.m., and many states start their restrictions at sundown.

The Insurance Institute for Highway Safety maintains a calculator, which finds what percentage of fatal and non-fatal crashes states could avoid by altering different aspects of licensing laws.

For Iowa, reducing the number of allowed teen passengers to zero could reduce the number of fatal crashes by 21 percent, and raising the permit age to 16 could cut it by another 24 percent.

Overall, bringing licensing laws up to national standards, best practices could help reduce fatal teen crashes by 55 percent, according to the Insurance Institute.

“We have an interest in maintaining parental rights,” Weinholzer said. “But once your child is on a public roadway where other people’s children, parents, and spouses are — when their lives are at risk because of your teenager’s behavior — it’s a societal issue, not a parental issue.”