How We Lost 90% of Participants on a Bad Bet: Results from a Pilot Randomized Controlled Trial on Cognitive Bias Modification in Problem Gamblers

Whilst opportunities to participate in gambling have increased, access to support for problem gamblers is lacking behind. This lack of balance calls for improved and accessible intervention methods. The present double-blind randomized controlled trial (RCT) explored the effectiveness of two interventions targeting automatic cognitive processes, known as Attentional Bias Modification (AtBM) and Approach Bias Modification (ApBM). It was hypothesized these interventions would reduce gambling behavior and reduce or reverse targeted biases. Participants (N = 331) were community-recruited Flemish (35%) and Dutch (65%) adult problem gamblers motivated to reduce or stop their gambling who received either six sessions of active training (AtBM or ApBM) or of the corresponding sham-training (sham-AtBM or sham-ApBM). Due to high attrition rates (90.1% up to the intervention phase) the study was terminated before completion, since it would greatly limit the validity of any results. A post hoc qualitative study was performed on a subset of participants to gain insight into contributing factors for the high attrition rate. Issues negatively impacting participants’ motivation to complete the program were identified, as well as elements of the program that received approval. The results from this study provide a first insight into the potential of the use of online cognitive bias modification (CBM) interventions in problem gambling (PG). Suggestions and directions for future studies are discussed.