WEDNESDAY, Oct. 19, 2016 (HealthDay News) -- Speeding is the most common deadly mistake new teen drivers make, and parents don't do enough to help their children drive safely, traffic safety experts say.

Nearly 14,000 fatal crashes involving teen drivers in the United States occurred over the past five years. Speeding was a factor in more than 4,200 of those crashes, according to the American Automobile Association (AAA).

"Involved parents really can help save lives, so it's important for parents to coach their teens to slow down, as well as to avoid other common mistakes," Bill Van Tassel, AAA's manager of driver training operations, said in a news release from the association.

A survey of 142 driving instructors nationwide revealed the top three mistakes made by teens when learning to drive:

  • Driving over speed limits or too fast for road conditions.
  • Being distracted by a cellphone, passengers or by something else in the car.
  • Not properly scanning the road for risks or hazards.

Also, 65 percent of the driving instructors said that parents today are worse at preparing their teens to drive than a decade ago. And it doesn't help that many adult drivers report dangerous behind-the-wheel behaviors themselves.

"Nearly two-thirds of people injured or killed in a crash involving a teen driver are people other than the teen," Van Tassel said.

Jennifer Ryan, director of state relations for AAA, agreed that the combination of inexperience and risk-taking can be deadly.

"Parents need to understand the common mistakes teens are making and take the time to help their teens learn how to stay safer on the road when they are learning to drive," she said.

Previous research found that teens whose parents impose stricter driving limits have fewer traffic violations and crashes. The AAA outlined ways parents can help teens who are learning to drive.

These include: regular discussions about the dangers of speeding and distractions; practicing driving with teens in varying conditions; creating and enforcing an agreement about driving rules; and leading by example.

A survey of drivers aged 35 to 55 found that 77 percent used a cellphone while driving, and 46 percent reported driving 15 miles per hour over the speed limit on the highway.

"Parents play a major role in keeping our roads safe," Ryan said. "Most teens are learning important driving skills from watching their parents and they are picking up bad behaviors along with the good ones. So it's up to today's parents to set a good example. It may end up saving their children's lives."

More information

The U.S. Centers for Disease Control and Prevention has more on teen drivers.