Behavioural activation as predictor of substance use: mediating and moderating role of attitudes and social relationships.

Alcohol, tobacco, and drug use were investigated in 4,501 Russian youths aged 14-25 years. The participants also filled out the short forms of the Gray-Wilson Personality Questionnaire and the Eysenck Personality Questionnaire along with questions about attitudes and social relationships. Behavioural Activation (BAS) was the best personality predictor of substance use. Its influence was mediated by disobedience to adults, affiliation with peers (Outings) and tolerant attitude toward illegal activity. BAS was negatively associated with subjective well-being and educational aspiration (Learn). Extraversion was the second strongest predictor of substance use with its influence being mostly mediated by Outings. Besides, Extraversion was positively associated with some protective factors such as subjective well-being, Learn and good relationship with parents. Effects of Neuroticism and Behavioural Inhibition (BIS) on substance use were weak and gender-specific. In females BIS provided a degree of protection while in males it increased the risk of substance use. The personality factors interacted so that BAS and Extraversion tended to mutually increase the impact of each other, while BIS diminished the effect of BAS. Among attitude variables, Outings acted as the most potent predictor of substance use. Relationship with parents was a protective factor, which acted most strongly in adolescents with higher Psychoticism and Extraversion.