Motivational Interviewing: An Evidence-Based Approach for Use in Medical Practice

Background: Motivational factors in health-relevant modes of behavior are an important matter in medical practice. Motivational interviewing (MI) is a technique that has been specifically developed to help motivate ambivalent patients to change their behavior. Methods: This review is based on pertinent publications retrieved by a selective search in the PubMed, Cochrane, and Web of Science databases. Special attention was paid to systematic reviews and meta-analyses concerning the efficacy of MI in the medical care of various target groups. The present review focuses on the relevance of MI for patients with highly prevalent disorders. Results: Meta-analyses reveal statistically significant mean intervention effects of MI in medical care with respect to a variety of health-relevant modes of behavior, in comparison to standard treatment and no treatment in the control groups (odds ratio [OR]: 1.55; 95% confidence interval: [1.40; 1.71]). Statistically significant effect sizes were reported for substance consumption, physical activity, dental hygiene, body weight, treatment adherence, willingness to change behavior, and mortality; effects on health-promoting behavior were mixed. Studies of the factors that contribute to the efficacy of MI suggest that it exerts its effects largely through the selective reinforcement of statements made by the patients themselves about potential changes in their behavior. Conclusion: MI has been found useful for strengthening the motivation for behavioral change in patients with various behaviorally influenced health problems and for promoting treatment adherence. It can be used to optimize medical interventions. Further research is needed with respect to its specific mechanisms of action, its efficacy in reinforcing health-promoting modes of behavior, differential indications for different patient groups, and the cost-efficiency of the technique across the spectrum of disorders in which it is used.