Among the explanations for the decline in smoking, Professor Johnston said, were increasing prices, less tobacco advertising and more anti-smoking advertisements.

In one study, an anti-smoking advertisement was shown before a feature film.

While anti-smoking advertisements carry no guarantees, they can be fairly effective under controlled circumstances.

The messages and executions of anti-smoking advertisements intended to lower adolescent smoking prevalence should be geared towards adolescents.

Some nations, including the UK and Australia, have begun anti-smoking advertisements to counter the effects of tobacco advertising.

The FCC decision, upheld by the courts, essentially required television stations to air anti-smoking advertisements at no cost to the organizations providing such advertisements.

Last year, a proposal to ban smoking in schools and to require the tobacco industry to help pay for anti-smoking advertisements failed in the state Senate.

He also directed a series of anti-smoking advertisements, one for Nicorette in 2006 and two for Niquitin in 2008.

"I believe it," she said of the anti-smoking advertisements.

One anti-smoking advertisement shows an elderly woman with an air hole (from cancer) in her throat smoking a cigarette through the hole.