A Dismantling Study of Dialectical Behaviour Therapy (DBT) Skills: Investigating the Effectiveness of Distress Tolerance, Emotion Regulation, and Interpersonal Effectiveness Skills Groups

BRIEF NAME Dialectical Behaviour Therapy (DBT). WHY DBT is an efficacious treatment for reducing suicidality and nonsuicidal self-injury among patients with Borderline Personality Disorder (BPD). WHAT In the standard DBT model, DBT skills and strategies are taught throughout 6-12 months of weekly 2.5-hour skills groups, weekly one-hour individual therapy sessions, between-session phone coaching, and a weekly consultation group for therapists. Standard DBT consists of three modules - Distress Tolerance, Emotion Regulation, and Interpersonal Effectiveness. Distress Tolerance module is 8 weeks, Emotion Regulation Module is 10 weeks and Interpersonal Effectiveness Module is 7 weeks. PROCEDURES The study involves patients of three adult mental health services across five hospitals in Queensland, who have a diagnosis of BPD, and who are completing standard DBT. We will administer outcome questionnaires to participants at five time-points. This is a controlled trial with three active arms and one control group. Arm 1 Princess Alexandra Hospital Logan Hospital Arm 2 Royal Brisbane and Women's Hospital Group 1 Royal Brisbane and Women's Hospital Group 2 Note - participants are allocated to the two RBWH groups based on capacity in each group as well as client preference for group day and time (Group 1 runs on a Wednesday, Group 2 runs on a Thursday). Arm 3 The Prince Charles Hospital Caboolture Hospital WHO Psychologists, social workers and mental health nurses who have been intensively trained in delivering standard DBT. MODE OF DELIVERY Face-to-face NUMBER OF TIMES DBT is delivered twice per week for six months. Data are collected at five time-points: Diagnostic and suitability assessment Time 1: prior to commencing treatment Time 2: following completion of the first module of DBT Time 3: following completion of the second module of DBT Time 4: following completion of the third module of DBT. LOCATIONS Princess Alexandra Hospital Logan Hospital Royal Brisbane and Women's Hospital The Prince Charles Hospital Caboolture Hospital ADHERENCE For group DBT sessions, adherence will be measured by group facilitators monitoring their own adherence utilising eight-item adherence checklists developed for this study; and 10% of skills groups will be independently coded via live observation by an intensively trained DBT clinician.