Teen drinking and driving rates have dropped by 54 percent over the last two decades, however, that still means that 1 million teens drank and drove in 2011, according to a new report.

Among teen drivers who were involved in fatal crashes in 2010, 1 in 5 had some alcohol in their system, and 81 percent had blood alcohol levels over the legal limit for adults, according to the report from the Centers for Disease Control and Prevention.

Binge drinking, which was defined as having at least five alcoholic drinks within a few hours, was reported by 85 percent of high school teens who noted drinking and driving in the past month.

“We are moving in the right direction,” said Dr. Thomas R. Frieden, the CDC director. “But we must keep up the momentum,” because 1 in 10 high school teens drinks and drives each month, endangering themselves and others.

For the report, CDC researchers analyzed data gathered during the Youth Risk Behavior Surveys between 1991 and 2011. In these national surveys, high school students were asked if they had driven a vehicle after drinking alcohol at least during the previous 30 days.

Drinking and driving rates were generally higher among males than females, and were highest among males age 18 and older. In this group, 18 percent reported drinking and driving in the past month.

Parents' efforts to get involved in their teens' lives can help keep them safe, according to the report. Parents can model safe-driving behavior and use tools such as parent-teen driving agreements.

Research has also shown that laws establishing a minimum legal drinking age, zero tolerance laws and a graduated driver-licensing system can protect teen drivers.

Pass it on: Drinking and driving rates have dropped among teens, but large numbers still imbibe and then get behind the wheel.

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