Adaptation of Individual Dialectical Behavior Therapy Intervention for Transdiagnostic Treatment of Emotional Disorders

Anxiety and depressive disorders, referred to as emotional disorders, have high rates of prevalence, recurrence, and functional impairment. Transdiagnostic psychotherapy targeting shared features of these disorders has recently emerged. Dialectical behavior therapy (DBT) for the transdiagnostic treatment of emotional disorders is a promising approach, as results of preliminary studies for use in a broad range of mental disorders are encouraging. Since there is a lack of research on transdiagnostic psychotherapy in Taiwan, the investigators thus propose this 3-year randomized controlled trial to test the efficacy of a modified DBT for the treatment of transdiagnostic emotional disorders and to further evaluate whether the efficacy of modified DBT differs in the specific emotional disorders. The investigators expect that patients with emotional disorders receiving modified DBT are more likely to improve clinical outcomes, functioning, and quality of life.

Anxiety and depressive disorders, referred to as emotional disorders, have high rates of prevalence, recurrence, and functional impairment. Transdiagnostic psychotherapy targeting shared features of these disorders has recently emerged. Dialectical behavior therapy (DBT) for the transdiagnostic treatment of emotional disorders is a promising approach, as results of preliminary studies for use in a broad range of mental disorders are encouraging. Since there is a lack of research on transdiagnostic psychotherapy in Taiwan, the investigators thus propose this 3-year randomized controlled trial to test the efficacy of a modified DBT for the treatment of transdiagnostic emotional disorders and to further evaluate whether the efficacy of modified DBT differs in the specific emotional disorders. This 3-year intervention trial has a randomized, controlled, two-center, and single-blinded design with two parallel groups. The trial will be conducted in the psychiatry departments of two medical centers, employing identical protocols. Participants will be recruited and randomly allocated 1:1 to one of two study arms. The modified DBT protocol in an individual therapy format consists of 12 weekly individual sessions, each lasting 50 minutes. A minimum of 250 participants will be included based on sample size estimation. Assessments will take place before the start of the trial, at the end of the trial, and at a 3-month follow-up. Primary outcomes will be the severity of depression and anxiety, rated by blind assessors. Secondary outcomes include disorder-specific symptoms, disorder severity, functional impairment, quality of life, and emotion regulation biases. The investigators will also examine the treatment mechanisms and treatment processes.

Eligibility Criteria:
Inclusion Criteria:

1. Mandarin Chinese-language proficiency sufficient to complete study questionnaire
2. A current diagnosis of depressive or anxiety disorder as diagnosed from a SCAN interview

Exclusion Criteria:

1. Intellectual disability
2. Substance use disorder in the past three months
3. Bipolar disorder
4. Psychotic disorder
5. Organic brain disorder
6. Acute suicidality or a history of frequent or recent suicide attempts
7. Recent (past six weeks) change in psychiatric medication or unwillingness to maintain a stable dosage of medication during study participation
8. Had received five or more sessions of CBT in the past five years or unwilling to stop concurrent psychotherapy for an emotional disorder
9. Any mental or physical condition requiring hospital admission
10. Another medical condition likely to prevent participation in the study