Pierce 2010.

Methods	Cohort study Baseline survey: September 2003‐ October 2004 Follow‐up: 8‐month intervals (April 2004‐October 2005; May 2005‐July 2006; April 2006‐April 2007; July 2007‐September 2008) Site: USA Research Question: Do cigarette advertising campaigns conducted after the MSA continue to influence smoking among adolescents? Analysis: Logistic Regression assessed which baseline variables predicted smoking initiation at final follow‐up. Controlled for randomised group assignment as well as gender, age, race, geographic region, school performance, single‐parent home, parental education, peer smoking, family smoking and susceptibility to smoking. Estimates were weighted to be representative of the US population and to minimize non‐response bias.
Participants	National sample of 1036 adolescents, 10‐13 years, were surveyed at baseline (71.8% were retained through survey 5). 937 were categorized as baseline never smokers (73% or 681 completed all 5 surveys). Average age was 15.7 years at final follow‐up Survey method: 5 telephone surveys
Interventions	Receptivity to tobacco advertising was measured by naming the cigarette brand of your favourite cigarette advertisement. Respondents who said no were also asked: "Of all the cigarette advertisements you have seen, which do you think attracts your attention the most?" 5th interview took place 4‐months after RJ Reynolds Camel No. 9 advertising campaign
Outcomes	Having smoked was a classified as a positive response to "have you ever smoked a cigarette?" or "have you ever tried or experimented with cigarette smoking, even a few puffs?" Never Smokers answered no to the above questions. Smoking initiation by baseline never smokers was assessed at survey 5
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