There was clearly a link between the film industry's inclusion of smoking in movies and the prevalence of adolescents trying -- as well as regularly using -- tobacco. As Sargent remarked, "The results led to a policy question: what could you do about it?"

And after more intensive research, Sargent and his team found their answer: movie ratings.

Enlisting just over 6,500 adolescents, the researchers followed up with longitudinal surveys, checking in with the participants at eight month intervals, and using a survival model to estimate the length of time before an onset of smoking.

Movie smoking exposure (or MSE) was evaluated based upon the viewing of 532 recent box office hits. Each movie was categorized according to the respective ratings assigned by the Motion Picture Association of America: G/PG, PG-13, and R.

Although the median MSE was three times higher for PG-13 films compared to that of R-rated films, their relation to smoking was absolutely the same. These results lead to a surprising conclusion -- and one that effectively dismissed past research: it was the smoking itself that motivated adolescents to try tobacco, not the risky or flashy behaviors often included in and associated with adult movies. Or, as stated by the study:

The equivalent effect of PG-13-rated and R-rated MSE suggests that is the movie smoking that prompts adolescents to start smoking, not other characteristics of R-rated movies or adolescents drawn to them.

From this conclusion, Sargent and his colleagues were able to infer that giving an R rating for any movie showing smoking "could substantially reduce adolescent smoking." He proposes it might even reach an 18 percent decrease (a figure based off of risk estimations, probabilities of smoking onset, and the above MSE levels).

So, Sargent ultimately calls on the movie industry to take the same measures as they do in considering scenes of violence, sex, profanity, etc. That said, he still recognizes that the new implementation would "constrain the industry which looks to reach the largest audience possible."

Although this study offers valuable evidence as well a possible option for reducing adolescent smoking, it still leaves us with several notable uncertainties.

Sure, a new R rating might reduce smoking onset in adolescents, but wouldn't it simply postpone the eventual adoption of tobacco use? Or are adolescents that much more impressionable than their over-18 "adult" selves? The rating might forestall things, but it may be incapable of preventing the inevitable.

When asked about this possibility, Sargent agreed that this perspective could be a small glitch in the study's conclusions. But, he argued that older teenagers (17 and above) are "able to make more informed choices about what they're going to do." They would ideally have a higher maturity level and an improved capacity to make better decisions regarding health. "We don't hold kids at 12 or 13 entirely responsible for their decisions, but [with older teenagers], there's less of a chance of responding to stimuli in movies."

Conceding that logic, the Norris Center's study seems to provide a well-founded conclusion and a plausible recommendation. Your move, movies.

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