On gender and TMT-A. The REM-ACT study: Acceptance and commitment therapy versus a mindfulness-based emotional regulation intervention in anxiety disorders. A randomized controlled trial

Abstract

Introduction: There is a paucity of studies which address the relationship between mindfulness and cognitive flexibility. This is the first study to compare two mindfulness-based interventions on this cognitive function. Objective(s): To compare the effectiveness of Acceptance and Commitment Therapy (ACT) versus a Mindfulness-based Emotional Regulation (MER) intervention on cognitive flexibility. Method(s): This study was carried out in a Mental Health Unit (Colmenar Viejo, Madrid). Firstly, 52 adult patients with anxiety disorders were randomized according to the score on the Acceptance and Action Questionnaire-II (blocking factor), of whom, 39 patients decided to participate (age range: 21-63 years). Each intervention was weekly, during 8 weeks, guided by two Clinical Psychology residents. A 2x2 mixed ANOVA (pre-post change x intervention type) was conducted, with Sidak-correction post hoc tests. The dependent variable was the score on the TMT-B (seconds). Result(s): A transformation according to the natural logarithmic function was conducted due to normality violation regarding the post-intervention measure. Homoscedasticity assumption was met. No statistically significant differences between interventions were observed on the pre-treatment score (t(36) = -0.28, p = 0.78). A statistically significant interaction effect was observed [F(1, 33) = 8.00, p = 0.01, partial eta-squared = 0.20, statistical power observed = 78.4%], showing significant improvement after ACT but not after MER. The Mann-Whitney test, on the difference pre-post scores, confirmed such improvement after ACT (p = 0.02). Conclusion(s): These results show a differential change pattern between both mindfulness-based interventions regarding cognitive flexibility. A larger sample size is required to confirm these results.