Direct, mediated and moderated impacts of personality variables on smoking initiation in adolescents.

Role of 'Big Five' personality traits as predictors of smoking and moderators of the intention-smoking relationship was tested. Five hundred and fifty-three adolescents (aged 11-12) completed measures of self-reported past smoking, gender, intentions to smoke, perceived behavioural control, family smoking, friends smoking at times 1 and 2 (6 months apart). At time 3, 2 years later, the same adolescents completed measures of the Big Five and self-reported smoking (a subset of 300 also provided an objective smoking measure). At time 4, two years after time 3, a sub-sample of 122 adolescents provided a self-report measure of recent smoking. Simple correlations indicated significant direct effects of conscientiousness (self-reported smoking, times 3 and 4), extraversion (time 4 smoking) and neuroticism (all smoking measures) on smoking. Logistic regression showed intention, and the interaction between conscientiousness and intention to significantly predict both self-reported and objectively assessed smoking (both at time 3) after controlling for other variables. Multiple regression showed intentions, family smoking and the interaction between conscientiousness and intention to significantly predict self-reported smoking at time 4 after controlling for other variables. The findings indicate that the impact of personality variables on smoking is through mediated (through cognitions) and moderated (conscientiousness by intention interaction) pathways.