Effectiveness of Group and Individual Formats of a Combined Motivational Interviewing and Cognitive Behavioral Treatment Program for Problem Gambling: A Randomized Controlled Trial

Background: The study aimed to assess the effectiveness of group and individual formats of a combined motivational interviewing and cognitive behavioral treatment (CBT) program for problem gamblers (PGs) using a randomized controlled design. Method: One hundred and two PGs were randomly assigned to individual or group CBT conditions. Twenty-eight of these participants were randomly allocated to a 6-week waitlist control condition prior to receiving the designated treatment. Results: At post-treatment, there were significant improvements in all dependent variables (frequency and amount gambled, gambling urges, gambling cognitions, negative psychological states, and life satisfaction) for both the treatment conditions but not for the waitlist condition. Individuals that completed the individual (compared to group) treatment condition generally had higher effect sizes for gambling correlates. Therapeutic gains for gambling correlates were generally maintained at 6-month follow-up. Conclusions: A combined motivational interviewing and CBT program applied in group or individual format can improve PG behaviors, as well as gambling correlates.