Several studies have shown that distractions while driving, such as using cell phones or texting, can be dangerous. New research confirms these findings among teens.

The study of 21 teens in a driving simulator found that while texting or searching their MP3 music players they changed speed dramatically, wove in an out of their lanes, and, in some cases, ran over virtual pedestrians.

Similar studies have found that adults who talk on cell phones while driving in simulators perform as dismally as drunken study participants. Studies from the University of Utah show that hands-free devices do not make it safe to use cell phones while driving.

In January, the National Safety Council called on state and federal lawmakers to ban the use of cell phones and text-messaging devices while driving and also urged businesses to prohibit it.

The problem is acute among younger people.

Motor vehicle accidents are leading cause of death for people between 16 and 20, accounting for more than 5,000 deaths each year, according to the Centers for Disease Control and Prevention. Teens are four times more likely than older drivers to be involved in a crash.

The new study included 21 subjects between 16 and 18 years of age with at least six months driving experience. Anyone diagnosed with an attention disorder or with history of unsafe driving was excluded, as were teens who reported use of alcohol or excessive amounts of caffeine. Each driver completed four separate 10-minute driving blocks: Undistracted, talking on a cell phone, text messaging and using an MP3 player. Each 10-minute block was separated into two separate driving scenarios, rural and urban.

The results for the teens sending text messages or fiddling with their MP3 players showed increased "lane position deviation" and speed changes, mostly slowing down.

"What this study demonstrates is that not only does your speed go up and down, you're swinging wide left and right," said Dr. Donald Lewis, of the Eastern Virginia Medical School and Children's Hospital of the King's Daughters in Norfolk, Va.. "You're a hazardous driver, to yourself and everybody else."

The findings were presented to the Pediatric Academic Societies May 2.