Development and differentiability of three brief interventions for risky alcohol use that include varying doses of motivational interviewing

Abstract

Background While brief intervention (BI) for risky alcohol use generally yields positive effects among those identified by screening, effect sizes are small and there is unexplained heterogeneity in outcome. The heterogeneity may be related to differences in intervention style and content, including elements of motivational interviewing (MI). To date, it has been difficult to interpret the role of MI in BI and these gaps in knowledge interfere with efforts to train, disseminate and implement BI that retains and maximizes efficacy. This study sought to develop BI protocols with varying doses of MI and test their differentiability. Differentiable BI protocols could allow for future studies that prospectively evaluate the role MI plays in affecting BI outcome.MethodsWe developed three intervention protocols: brief advice, standard BI (NIAAA Clinician’s Guide), and MI-enhanced BI and administered them to 45 primary care patients who reported exceeding recommended drinking limits. We then rated the BI sessions for fidelity to the assigned protocol as well as MI consistency based on Motivational Interviewing Treatment Integrity (MITI) scale scores. The differentiability of BI protocols was determined by calculating fidelity to assigned protocols and comparing MITI scores using pairwise, Tukey-adjusted comparisons of least squares mean scores.ResultsHigh rates of fidelity to each protocol were achieved. The three BI protocols were also highly differentiable based on MITI scores.Conclusions The three interventions can be used in future trials to prospectively examine the role MI has in determining BI outcome.Trial registration clinicaltrials.gov NCT02978027, retrospectively registered 11/28/16Electronic supplementary materialThe online version of this article (10.1186/s13722-017-0102-0) contains supplementary material, which is available to authorized users.

Lessons learned from measuring fidelity with the Motivational Interviewing Treatment Integrity code (MITI 4)

“…Low variation in the measures will decrease the ability to obtain high levels of calculated interrater reliability (Hallgren, 2012). Since this has made it difficult to obtain high levels of calculated interrater reliability for the global scores (Hallgren, 2012;Hettema et al, 2018;Seng & Lovejoy, 2013;Spohr, Taxman, Rodriguez, & Walters, 2015), we looked into the data being compared when low ICC's were reported for the global measures. A difference of one or less on the five-point Likert scale in the rated recordings was in these cases considered an acceptable agreement.…”

“…Like the rating of empathy in the analysis of ICC based on 11 sessions and only two raters, the ICC takes into account the high chance of the raters agreeing on a four; therefore, the ICC is low even when raters agreed on four in most of the cases. Difficulties in attaining high ICCs without the whole range of the Likert scale being utilized is not new (Brueck et al, 2009; J. E. Hettema et al, 2018;Seng & Lovejoy, 2013;Spohr et al, 2015). The ICC is simply not a good measure of agreement in such cases.…”