Susceptibility to smoking among South East Asian youth: a multilevel analysis

OBJECTIVE: To estimate the extent to which susceptibility to smoking is associated with between-context differences (schools and classes) and to identify factors at school, class and individual levels that influence individual susceptibility to smoking among young never-smokers in South East Asia. METHODS: Cross-sectional data from the Global Youth Tobacco Survey conducted in Cambodia (2002), Laos (2003) and Vietnam (2003) are used to conduct multilevel analyses that account for the nesting of students in classes and classes in schools. The outcome variable is smoking susceptibility, defined as the absence of a firm decision not to smoke. Explanatory variables include school-level (current tobacco use prevalence in school, exposure to anti-smoking media messages and exposure to tobacco billboard advertising), class-level (classroom prevention) and individual-level influences (parents' and friends' smoking behaviour, knowledge of the harmful effects of and exposure to secondhand smoke at home, age, sex and pocket income). RESULTS: Multilevel analyses indicate that 4.5% and 4.2% of the variation in smoking susceptibility is associated with school and class differences, respectively. Students who have parents or friends who smoke, who are exposed to secondhand smoke at home and those who have access to pocket income are found to be more susceptible while greater knowledge of the harmful effects of secondhand smoke appears to diminish susceptibility to smoking. For girls only, billboard tobacco advertising increases the risk of susceptibility and classroom prevention decreases risk while for boys only, attendance at schools with higher prevalence of tobacco use increases risk of susceptibility and anti-smoking media messages decreases risk. CONCLUSIONS: This study highlights a number of modifiable factors associated with smoking susceptibility and identifies interactions between teen sex and several factors associated with the susceptibility to smoking. This finding provides support for the call to move beyond gender-blind tobacco control policies.