Hey, Mom and Dad, the axiom "Do as I say, not as I do" turns out to be a pretty inadequate way to teach teen drivers how to be safe behind the wheel.

A new study by a national insurance company and Students Against Destructive Decisions reveals that many of you tell your child not to drive and text or talk on the phone, but you do it ("What should I pick up for dinner?"), AND you insist your teen answer the phone whenever you call - no exceptions.

The result of these mixed messages? Your inexperienced teen driver ends up using his or her cellphone while negotiating through traffic.

A cellphone is involved in 21 percent of teen crashes (11 percent for adults) and distracted driving causes 11 percent of fatal teen accidents. Yet more than 85 percent of licensed high-school students admit to using a cellphone while driving.

So before your bad example and phone-answering rules steer your kid into trouble, here are a few tips on how to improve driving safety:

• When your teen does talk to you, ask immediately if he or she is driving. Yes? Ask for a call back when the car is stationary. Then hang up.
• Make it a whole-family rule not to text or talk on the phone while driving, because on a cellphone actions speak louder than words.
• Devices and apps are available for you to see if your teen is following rules about phone use (and speeding). These may qualify you for a car-insurance discount.

© 2014 Michael Roizen, M.D. and Mehmet Oz, M.D.
Distributed by King Features Syndicate, Inc.