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

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.