Objective: To assess whether smoke-free restaurant laws influence the progression from (1) never smoking to early experimentation and (2) early experimentation to established smoking.
Design: A longitudinal, 4-year, 3-wave study of a representative sample of Massachusetts youth.
Setting: A total of 301 Massachusetts communities.
Participants: Study participants were 3834 Massachusetts youths aged 12 to 17 years at baseline, from January 2, 2001, to June 18, 2002, of whom 2791 (72.8%) were reinterviewed after 2 years (from January 30, 2003, to July 31, 2004) and 2217 (57.8%) were reinterviewed after 4 years (from February 16, 2005, to March 26, 2006). Wave 3 respondents were recruited from both those who responded at wave 2 and those who did not.
Main exposure: The primary predictor of interest is the strength of the local restaurant smoking regulation in the respondents' town of residence at the baseline of each transition period.
Main outcome measures: (1) Overall progression to established smoking (having smoked > or =100 cigarettes in one's lifetime), (2) transition from nonsmoking (never having puffed a cigarette) to experimentation, and (3) transition from experimentation to established smoking.
Results: Youths living in towns with a strong restaurant smoking regulation at baseline had significantly lower odds of progressing to established smoking (odds ratio, 0.60; 95% confidence interval, 0.42-0.85) compared with those living in towns with weak regulations. The observed association between strong restaurant smoking regulations and impeded progression to established smoking was entirely due to an effect on the transition from experimentation to established smoking (odds ratio, 0.53; 95% confidence interval, 0.33-0.86).
Conclusion: Local smoke-free restaurant laws may significantly lower youth smoking initiation by impeding the progression from cigarette experimentation to established smoking.