Motivational interviewing: living up to its promise?

Abstract

Motivational interviewing is a form of psychotherapy in which ambivalence towards an aberrant behaviour is targeted. Rather than challenge the behaviour directly, the clinician encourages the patient to devise a list of problems that are caused by the behaviour and to identify solutions. There are many trials of motivational interviewing, although it has been most studied as treatment for substance misuse. The effect sizes for motivational interviewing are small, they probably diminish over time, the trials often use multiple outcome measures and the outcomes of some very large trials have been disappointing. Large effects are occasionally reported, although these tend to be from small trials conducted by highly motivated research groups and the results tend to diminish when the trials are repeated or enlarged. Nonetheless, motivational interviewing is a well-validated approach supporting and enabling engagement in therapeutic process. It could be argued that even though it might not be as efficacious as a primary/stand-alone means of changing patients’ behaviour, it can still be highly effective when combined with other approaches or used as a conduit to a more intensive therapy.