Chapter 1. General introduction -- Chapter 2. The role of moral disengagement in underage drinking and alcohol-related harm -- Chapter 3. Adolescents' anticipated social outcomes from mothers, fathers, and peers for drinking alcohol and being drunk -- Chapter 4. The influence of underage drinking disengagement and anticipated social outcomes for being drunk on adolescents' alcohol use and experience of alcohol-related harm -- Chapter 5. General discussion.
To investigate the role of social cognitive processes in underage drinking, this thesis presents three studies which examined two social cognitive processes (moral disengagement and anticipated social outcomes) and how they relate to adolescents' engagement in underage drinking and experience of alcohol-related harm. The first study, based primarily on a sample of 636 (386 females) adolescents (14-17 years), developed a reliable and valid Underage Drinking Disengagement Scale (UDDS). Further, moderated mediation analyses revealed that associations between negative evaluations about underage drinking, anticipatory guilt, and engagement in underage drinking, or experience of alcohol-related harm, were weaker at high compared to low scores on the UDDS. In the second study, based on data collected from 651 (329 female) adolescents (12-16 years), two scales assessing the social outcomes adolescents anticipate for drinking alcohol (Drink ASO Scale) and for being drunk (Drunk ASO Scale) were developed. For each scale, factor analyses confirmed separate sub-scales representing anticipated social outcomes for mothers, fathers, and peers. Additionally, results revealed that anticipation of less social censure for drinking alcohol related to greater engagement in underage drinking, while for underage drinkers, less social censure for being drunk more strongly related to greater experience of alcohol-related harm. In the third study, participants, derived from the same sample as study two, were 347 (161 female) underage drinkers who were assessed at three time points, eight months apart. Latent growth modelling revealed that, across time, underage drinking disengagement and anticipated social outcomes for being drunk independently contributed to an increase in adolescents' alcohol use and experience of alcohol-related harm. The findings from this thesis highlight the importance of understanding how adolescents self-regulate their drinking and ways that such self-regulation may be disengaged. Further, this thesis highlights the self-regulatory influences of parents and peers on adolescents' use of alcohol and experience of alcohol-related harm.