Moderating influence of smoke-free air laws on smoking cessation behavior

Background: The number and scope of smoke-free air laws implemented around the world has increased dramatically, but how these laws influence smoking behavior is not well understood. We used a Theory of Planned Behavior framework to explore whether smoke-free air laws exert their influence through changes in attitude, subjective norm, or perceived behavioral control related to quitting. Methods: Participants were 395 adult smokers living in seven Texas cities, three with a comprehensive smoke-free air law and four without such a law. Data were collected by telephone administration of a questionnaire. We conducted two sequential multiple regression analyses, one for smokers living in a city with a comprehensive law and one for smokers living in a city without a law, predicting intention to take measures to quit smoking within the next month. We controlled for demographic factors and smoking behavior. Results: For smokers exposed to a comprehensive smoke-free air law, attitude (Beta=.436, p<.001), subjective norm (Beta=.232, p<.001), and perceived behavioral control (Beta=.248, p<.001) significantly predicted intention. For smokers not exposed to a comprehensive law, only attitude (Beta=.626, p<.001) and perceived behavioral control (Beta=.130, p<.05) significantly predicted intention. The difference between the regression coefficients for subjective norm for the two groups was marginally significant (p<.10). Conclusions: These findings suggest that smoke-free air laws may influence quitting behavior through changes in norms. Communication messages focused on how the laws reflect community norms against smoking and toward smokers taking measures to quit may be particularly effective in moving smokers toward cessation.