Assessing therapeutic change mechanisms in motivational interviewing using the articulated thoughts in simulated situations paradigm

Current evidence suggests that Motivational Interviewing (MI) can help to create behavior change in a variety of contexts, especially for those with alcohol use problems, but evidence is less clear on how and why MI seems to work. Using the Articulated Thoughts in Simulated Situations paradigm (ATSS), this study aimed to determine the mechanisms by which MI may modify the cognitions and behaviors of college-aged binge drinkers. Two mechanisms typical of an MI intervention were isolated, simulated, and analyzed: the presence of a warm/Rogerian therapist communication style and the use of a decisional balance exercise. By using a 2X2 design to compare these mechanisms to commonly used alternative therapeutic approaches, we sought to determine which mechanisms have the greatest impact on cognitions related to binge drinking and on intention to change, intention to drink, overall impressions of drinking, as well as actual changes in drinking behavior at a 30 day follow-up. As in a previous study, we found moderately strong evidence supporting the validity of the ATSS scenarios for our purposes. No significant effects were found on drinking behavior or any other variables at 30-day follow-up. However, as in the earlier study, the data show that, as compared to a more directive and confrontational communication style, the warm/Rogerian therapist style was associated with significantly fewer participant cognitions reflecting resistance to change during the ATSS scenario (a simulated therapy session) and with a temporary increase in readiness to change immediately after the scenario. We also found that, regardless of condition, higher levels of trait reactance increase the degree to which participants report that the therapist influenced them to think about not changing their drinking behavior. This study provides evidence that the warm/Rogerian therapist style advocated by MI is an important and active ingredient in psychotherapeutic process and, as such, should be a focus of clinical training and that attention to trait-like variables like reactance may help improve our understanding of MI and psychotherapy processes and outcomes in general. (PsycINFO Database Record (c) 2010 APA, all rights reserved)