Intolerance of uncertainty, social anxiety and alcohol use among students in the United Kingdom and Indonesia

PhD ThesisThis thesis principally aimed to investigate the precise role of IU in the development and maintenance of social anxiety and the relationship between IU, social anxiety and alcohol use. Furthermore, most of the findings of this thesis are original. A development and factor analyses of the Newcastle Substance Use Questionnaire (NSUQ), four independent cross-sectional studies and an experimental study were conducted. Non-clinical samples were recruited and entire studies were conducted online. The UK student sample study (university students; N = 349), the Indonesian study (N = 540) and also the replication of the UK student sample study (N = 200) reported that IU, FNE and AS each consistently made significant additive and unique contributions to the variance in social anxiety. The UK mixed sample study (N = 112) reported that both IU and FNE each made significant contributions, whilst shame did not. All the UK studies reported that IU contribution was the second greatest; whereas from the Indonesian study, the contribution of IU was the smallest. Each reported that the contribution of FNE was the greatest. Both the UK mixed sample and the UK student sample studies found that the effect of IU on social anxiety was significant only when FNE was intermediate to high. As FNE increased, the effect of IU in predicting social anxiety became stronger. The reversed analysis in the UK mixed sample study found that the effect of FNE on social anxiety was significant only when IU was intermediate to high, whereas in the UK student sample study it was significant at all levels of IU. Both studies reported that the effect of FNE on social anxiety became stronger as IU increased. The UK student sample study also reported that the effect of IU on social anxiety was significant at all levels of AS and it was augmented as the increasing of AS levels, whereas the effect of AS on social anxiety was significant only when IU was intermediate to high and it was augmented as the increasing the levels of IU. Moreover, the UK and Indonesian studies reported that FNE, IU and AS each consistently contributed to the variance in worry and depression symptoms. The UK study also found that the effects of IU on worry were significant at all levels of FNE or only when AS was low to high. The increase in FNE or AS decreased the impact of IU on worry. The reversed analyses found that the effects of either FNE or AS on worry were significant only when IU was low to high. Their effects became negative as IU increased. Furthermore, the experimental study (university students from the UK; N = 164) found that situational IU caused social anxiety and safety behaviours in the social interaction situation, although not in the social performance situation. It also provided evidence of x temporal precedence concerning the IU predisposition on safety behaviours in social interaction situation. It also provides evidence that the FNE predisposition influenced social anxiety and safety behaviours, in both situations. Unexpectedly, situational FNE was not effectively manipulated to cause social anxiety and safety behaviours. The factor analyses (participants of the UK student sample study; N = 285) reported that the three-factor solution of the alcohol section of the NSUQ was superior to other solutions and also interpretable. Social factor accounted for the most variance, followed by cognitive factor and lastly, sexual factor. Improving social interaction attained the highest rate and drinking alcohol with friends is the most frequent context. The UK student sample study and the replication also investigated the relationship between IU, social anxiety, social motives and alcohol use with friends. Both studies reported that the direct effects of IU, FNE and AS on drinking alcohol with friends were not significant. Moreover, the indirect effects of these cognitive vulnerabilities through social anxiety were significant and negative. Only the indirect effect of FNE through social motives was significant and positive. However, the indirect effect of IU through social anxiety and social motives serially was significant and positive, whereas the indirect effect of FNE was not significant. Overall, this thesis establishes the important role of IU, in conjunction with FNE and ASI, in predicting social anxiety; but also provides an initial evidence that IU may in fact have a causal role in social anxiety. Moreover, IU is a transdiagnostic factor which may underlie comorbidity across social anxiety and GAD. Lastly, this thesis reported that socially anxious students may be less inclined to participate in social activities and eventually less likely to take part in social drinking. However, they may be motivated by social reason to use alcohol as a social lubricant