EUGENE, Ore. - An Oregon State University study suggests that anti-smoking ads by the tobacco industry targeted at youths and their parents do not work and might actually encourage some teens to smoke.

At best, the ads have no effect, said Brian Flay, a professor in Oregon State's department of public health in Corvallis, one of nine researchers who studied tobacco-industry ads. He said some ads, particularly those aimed at parents, may actually encourage smoking.

Cigarette maker Philip Morris USA disputes the results. Philip Morris says not only has it spent $1 billion to develop and disseminate advertising aimed at deterring youth smoking but it also has research that shows the ads work. It says the ads are based on widely accepted research and don't carry hidden messages.

The new study appears in this month's issue of the American Journal of Public Health.

Researchers surveyed more than 100,000 youths in grades eight through 12 and focused on anti-smoking campaigns by Philip Morris that ran from 1999 to 2003. It used Nielsen Media Research data to determine the prevalence of anti-smoking ads and surveys conducted by schools to determine youth attitudes about smoking during that period.

The ads aimed at youths used the slogan "Think. Don't smoke" and told teens they didn't have to smoke to fit in. Those targeting parents urged them to talk with their children about the hazards of smoking and used the slogan "Talk. They'll listen."

The study was funded by the National Cancer Institute, the National Institute on Drug Abuse and the Robert Wood Johnson Foundation. The research team is part of Bridging the Gap, a joint program based at the University of Illinois at Chicago and the University of Michigan that focuses on youth health issues and public policy.

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