How counselors talk matters: change talk predicted marijuana use reduction | Research

The takeaway

When counselors used motivational interviewing techniques that elicited "change talk" from students, marijuana use decreased, supporting change talk as an active ingredient in this therapy approach.

Read this if you are interested in how counseling techniques actually work to reduce marijuana use.

Change talk mediated 3 of 4 pathways from counselor skill to reduced marijuana use

What the researchers found

Researchers analyzed 170 audio-recorded motivational interviewing (MI) sessions with alternative high school students. Using structural equation modeling, they found that the percentage of "change talk" (client language expressing desire, ability, reason, or commitment to change) mediated the relationship between counselor skill and marijuana use outcomes.

Specifically, when counselors demonstrated higher MI quality, students produced more change talk, which in turn predicted reduced marijuana use. This mediation pattern held for three of four MI quality indicators tested. Counselor reflections of change talk also showed a direct effect on marijuana outcomes.

The findings supported the theoretical model that change talk is an active ingredient in motivational interviewing, not just a byproduct of the therapeutic relationship.

Why it matters

Motivational interviewing is one of the most widely used approaches for addressing substance use, but the mechanisms through which it works have been debated. This study provided empirical support for the specific role of change talk, helping clinicians understand which conversational techniques actually drive outcomes.

The numbers in context

170 MI sessions were analyzed. Change talk mediated 3 of 4 relationships between MI quality indicators and marijuana outcomes. Counselor reflections of change talk showed a direct main effect on outcomes.

How the study worked

Data came from an MI booster intervention delivered to alternative high school students after a classroom-based drug abuse prevention program. 170 audio-recorded sessions were coded using the Motivational Interviewing Skill Code 2.5. Structural equation modeling tested whether change talk mediated the counselor skill to marijuana outcome pathway.

What this study cannot tell us

The sample was from alternative high schools, which serve students at higher risk for substance use and may not represent typical adolescents. The study examined marijuana use specifically and may not generalize to other substances. Observational coding of sessions involves subjective judgment.

How to read the evidence

Rigorous analysis of a randomized intervention with objective session coding, though limited to one high-risk population.

When this study was published

Published in 2014.

The bigger picture

Understanding why motivational interviewing works allows for better training of counselors and more targeted interventions. If change talk is the active ingredient, then techniques that specifically elicit change talk should be prioritized in counselor training for substance use interventions.

Questions still open

Does the change talk mechanism operate similarly for adult cannabis users? Can technology-based interventions elicit change talk effectively? How much change talk is needed to produce meaningful behavior change?

Common questions

What is change talk?

Change talk is language from a client that expresses desire, ability, reason, or commitment to change a behavior. In motivational interviewing, counselors use specific techniques to elicit this kind of language, which this study found predicted actual reductions in marijuana use.

Does motivational interviewing work for marijuana use?

This study provided evidence that it does, and identified change talk as the specific mechanism. When counselors used MI techniques well, students produced more change talk, which in turn predicted less marijuana use.

Read the original research

From counselor skill to decreased marijuana use: does change talk matter?

Journal of substance abuse treatment, 46(4), 498-505

View on PubMed ↗Publisher’s paper ↗

Citation

Barnett, Elizabeth; Moyers, Theresa B; Sussman, Steve; Smith, Caitlin; Rohrbach, Louise A; Sun, Ping; Spruijt-Metz, Donna. (2014). From counselor skill to decreased marijuana use: does change talk matter?. Journal of substance abuse treatment, 46(4), 498-505. https://doi.org/10.1016/j.jsat.2013.11.004