Over the past year, we’ve reported on the ineffectiveness — or, worse, counterproductive nature — of public-service announcements aimed at discouraging youngsters from smoking or using illegal drugs. But a new study suggests the advertising arena can be manipulated to lower teenage substance abuse.

The key, it appears, isn’t creating slickly produced warnings, but rather ensuring that teens aren’t exposed to advertisements that entice them to imbibe.

In a paper just published in the Journal of Safety Research, Ryan C. Smith and E. Scott Geller of Virginia Polytechnic Institute and State University examine the impact of state laws prohibiting alcohol advertising that targets minors. Using one particular type of alcohol-related traffic fatality as a measure, they found such statutes make a huge difference.

Using 2003 data from the Fatality Analysis Reporting System, the researchers did a state-by-state breakdown of drivers ages 15 to 20 who were killed in alcohol-related, single-vehicle traffic accidents. In these incidents, the driver was drunk and smashed into a tree, road sign or parked vehicle and was killed.

Smith and Geller selected single-car fatalities because it gave them “greater assurance” that the driver’s alcohol level was a factor in the crash. A two-car crash, after all, can be caused by the second driver, even if the first driver is drunk.

They then compared the rate of such accidents in the 24 states (and District of Columbia) that prohibit alcohol advertising that targets minors to that of the 26 states that did not have such laws on the books. Such statutes typically restrict where alcohol ads can be placed, how they are worded and whether they include symbols or drawings that appeal to youngsters.

States with these laws reported 32.9 percent fewer alcohol-related, single-vehicle traffic fatalities — nearly one-third fewer than those without such prohibitions. In contrast, the number of non-alcohol related traffic fatalities was not significantly different in the two sets of states. This suggests the statutes did decrease teenage alcohol consumption — or at least drinking and driving.

Smith and Geller estimate that if such a prohibition was enforced nationwide, an estimated 400 lives of young drivers could be saved every year. What, exactly, are the other states waiting for?

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