An Australian-led study has determined ads urging U.S. parents to talk with their children about the dangers of smoking only resulted in more young smokers.

The study, led by Melanie Wakefield of the Cancer Council Victoria in Melbourne, Australia, concluded youngsters 12 to 17 years of age were less likely to see smoking as harmful and after viewing the ads.

The slogan of the national campaign by cigarette industry leader Philip Morris USA of Richmond, Va., was "Talk. They'll listen."

Researchers analyzed TV ratings from 75 U.S. media markets and data from an annual national survey of eighth, 10th and 12th graders from 1999-2002.

The researchers determined youngsters likely to have seen the ads targeted at parents were more likely to believe the dangers of smoking had been exaggerated, The Washington Post reported.

Dave Sutton, a Philip Morris USA spokesman, told the Post of parents who saw at least one ad, 61 percent talked to their children about not smoking. "We have found nothing through our research to indicate that the study's conclusions are valid," Sutton said.

The study appears in the December issue of the American Journal of Public Health.

Copyright 2006 by United Press International