Supplementary Material for: Supported Mindfulness-Based Self-help Intervention as an Adjunctive Treatment for Rapid Symptom Change in Emotional Disorders: A Practice-Oriented Multicenter Randomized Controlled Trial

Introduction: Rapid symptom relief is crucial for individuals with emotional disorders. The current study aimed to determine whether facilitator-supported mindfulness-based self-help (MBSH) intervention as an adjunctive treatment could provide rapid improvement for individuals with emotional disorders. Methods: A practice-oriented randomized controlled trial was conducted in a sample of 302 patients with emotional disorders from four centers. Participants were randomly assigned to either MBSH+TAU (treatment as usual; n = 152) or TAU-only group (n = 150). Assessments were conducted at baseline, week 3, week 5, immediately after intervention and at a 3-month follow-up. Primary outcomes included self-reported and clinician-reported anxiety and depression symptoms. Secondary outcomes included mindfulness, physical symptoms, perceived stress, sleep quality, and inner peace. Results: The MBSH+TAU group achieved significantly greater improvements in all primary and secondary outcome measures as compared with TAU-only immediately after intervention (Cohen’ s d = 0.19-0.51). In addition, relatively greater improvements were observed in self-reported depression, mindfulness, physical symptoms, perceived stress, and inner peace as early as week 3 or 5, which were sustained at the 3-month follow-up (Cohen’ s d = 0.20-0.34). Conclusions: Facilitator-supported MBSH offers a scalable and effective adjunctive treatment option for patients with emotional disorders in clinical practice, facilitating rapid improvements.