The role of ambivalence and cognitive dissonance in motivational interviewing for alcohol problems

Motivational Interviewing (MI) has been shown to be an effective treatment for substance abuse and other lifestyle and/or behavioural problems. However, mechanisms of change remain a topic of speculation. It has been hypothesised that MI works by eliciting and resolving a client's ambivalence, thereby enhancing their motivation and commitment to change. Research has supported the theory that enhancing commitment is an integral element of MI, however little is known about the role ambivalence plays in producing change. The aim of this project was to investigate this role, and the possible role of other relevant models from social psychology such as cognitive dissonance. First, the social psychology literature relating to the process of ambivalence and dissonance was reviewed to determine whether this was adequately reflected in the literature on MI. It was found that a comprehensive, contemporary view of these processes is largely absent from the literature on MI, and that this may be potentially valuable in furthering an understanding of the mechanisms of change. Second, a secondary analysis of data from a completed randomized controlled study (the United Kingdom Alcohol Treatment Trial - UKATT) on the effectiveness of Motivational Enhancement Therapy (MET), an adaptation of MI, was carried out. This used a thematic analysis with an a priori coding frame based upon constructs shown previously by research in social psychology to be important in ambivalence and dissonance. The aim was to explore the relevance of these constructs to understanding the processes within sessions of MI, and to determine whether either the model of ambivalence or cognitive dissonance offers an advantage in analysing the data. Application of the a priori coding frame developed, to MET transcripts revealed variations in the expression of ambivalence and cognitive dissonance in client language. Inconsistencies both within and between the different cognitive components outlined in both theories occurred in close proximity to one another, inferring an experience of inconsistent related discomfort within the client. The thematic analysis also enabled the identification of additional themes, relevant to both ambivalence and cognitive dissonance theories, in client language. In total fourteen themes were identified, five ambivalence and nine cognitive dissonance. Ambivalence themes were expressed on 107 occasions and cognitive dissonance on 205. Ambivalence and cognitive dissonance theories prove to be valuable in examining and interpreting client language, providing a discrepancy-related model to enhance understanding of MI's motivational processes. It is concluded that cognitive dissonance more adequately captures the motivational processes reflected in client language: however ambivalence theory provides a more specific model, guiding clinicians and researchers delivering and investigating the elicitation and resolve of the ambivalent experience.