Effectiveness and mechanisms of internet-delivered transdiagnostic CBT for students with adjustment disorder: the role of cognitive inflexibility, self-compassion, and mindfulness

= 39). Assessments were conducted at baseline, post-treatment, and one-month follow-up. Outcomes included AjD, academic adjustment, experiential avoidance, self-compassion, and mindfulness. Daily diary assessments captured changes in self-compassion, mindfulness and psychological flexibility. Treatment effects were examined using mixed repeated-measures ANOVA and mediation analyses. Both active interventions significantly reduced AjD symptoms relative to wait-list, whereas only iCBT-UP improved academic adjustment. Reductions in experiential avoidance and increases in self-compassion mediated the effects of iCBT-UP on decreases in AjD symptoms. Self-compassion also mediated the effects of iCBT-UP on improvements in academic adjustment. Daily diary analyses showed increases in self-compassion and psychological flexibility in both active conditions. These findings support transdiagnostic CBT as an effective intervention for AjD and highlight key mechanisms of change.