Modified dialectical behavior therapy–informed transdiagnostic intervention for emotional disorders: protocol for a randomized controlled trial

Abstract Background Anxiety and depressive disorders, characterized by high incidence and functional impairments, are emotional disorders with shared etiological and maintenance mechanisms. Dialectical behavior therapy (DBT) is a promising approach for the transdiagnostic treatment of emotional disorders. Developing a brief DBT intervention can facilitate the adoption of evidence-based therapy. Methods This protocol is for a 3-year single-blinded, two-arm randomized controlled trial. Individuals with depressive or anxiety disorder will be randomly allocated to a modified DBT–informed transdiagnostic psychotherapy group or a treatment-as-usual group. The intervention group will receive DBT individual therapy for 15 weeks. Power analyses revealed that the cohort should include a minimum of 250 participants. Preintervention, postintervention, and follow-up (after 3 months) assessments will be conducted. Primary outcomes will be severities of depression and anxiety rated by blind assessors. Intent-to-treat and per-protocol analyses will be conducted using the hierarchical linear model. Effect sizes will be estimated using Cohen’s d. Result To the best of our knowledge, the proposed study will be the first randomized controlled trial to evaluate the efficacy of a modified DBT intervention in managing transdiagnostic emotional disorders in Chinese individuals. Conclusion This intervention is expected to improve clinical outcomes, daily functioning, and quality of life. The trial will enrich the empirical evidence for transdiagnostic interventions, facilitating the implementation of evidence-based therapy and reducing the high prevalence and challenges (e.g., disability) of emotional disorders in the Chinese population. Trial registration number NCT05989451