Extended Group Written Exposure Therapy for Comorbid PTSD and BPD (Traits)

The goal of this open label trial is to evaluate the effectiveness of virtual group extended Written Exposure Therapy (GE-WET) in reducing Post-Traumatic Stress Disorder (PTSD) symptoms in patients with comorbid PTSD and Borderline Personality Disorder (BPD) or BPD traits. GE-WET involves attending weekly 2-hour group WET sessions for the duration of 10 weeks, in which they write about their trauma experience using specific instructions.

This study will be conducted at St. Joseph's Healthcare Hamilton's Community Psychiatry Clinic with clients wait listed for PTSD treatment (ages 18- 65, any gender, co-morbid PTSD and BPD/BPD traits).

The main questions this study aims to answer are:

Does GE-WET reduce PTSD symptoms (based on PCL-5 measures) in this population (outpatient clients ages 18-65 of any gender, with a diagnosis of PTSD and BPD or BPD traits)?

Does GE-WET result in reduced drop-out rates for this population, compared to that of other evidence-based treatment for PTSD?

What are participants subjective experience of GE-WET?

Study Overview

• Status: Not yet recruiting
• Conditions: Posttraumatic Stress Disorder (PTSD); Borderline Personality Disorder (BPD)
• Intervention / Treatment: Behavioral: Group Written Exposure Therapy

• Study Type: Interventional
• Enrollment (Estimated): 63
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Canada
  • Ontario
    • Hamilton, Ontario, Canada
      • St. Joseph's Healthcare Hamilton

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Reading and writing proficiency in English
• Access to an electronic device to attend virtual group meetings
• Age 18-65
• Previous diagnosis of Posttraumatic Stress Disorder (PTSD) and Borderline Personality Disorder (BPD)/BPD traits
• Completion of a DBT skills group via St. Joe's Community Psychiatry Clinic

Exclusion Criteria:

• Diagnosis of an active severe substance use disorder or psychotic disorder
• Untreated active psychotic symptoms, mania, or hypomania
• Has attempted suicide in the 2 months prior to treatment beginning
• Has engaged in high-risk self-harm (e.g., cutting, burning, asphyxiation) in the 2 months prior to beginning treatment
• Has completed Cognitive Processing Therapy or another active PTSD treatment (i.e., prolonged exposure) in the past year

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: Group Extended Written Exposure Therapy; Participants will be invited to participate in group extended Written Exposure Therapy (described in the Interventions section).

Behavioral: Group Written Exposure Therapy; Group Extended Written Exposure Therapy (GE-WET) is a time-limited cognitive behavioural therapy for Posttraumatic Stress Disorder (PTSD) aimed at allowing patients to process their traumatic experiences in a safe environment. GE-WET will consist of 10 weekly group sessions. Participants will be asked to complete weekly in-session written exposures where they will recount their traumatic experience. The written exposure will be followed by a guided discussion about the experience of writing the exposure. There is no homework assigned between sessions. However, group members will be asked to refrain from avoiding thinking about the trauma between sessions.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
PTSD Checklist for DSM-5 (PCL-5)	From pre-treatment (1 week before the start of group) to one-month follow-up at about 4 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Posttraumatic Cognitions Inventory	A 36-item self-report questionnaire that assesses negative thoughts across three subscales: negative cognitions about the self (e.g., "I am a weak person"), negative cognitions about the world (e.g., "I have to be on guard all the time"), and self-blame (e.g., "the event happened because of the way I acted"). The PTCI has demonstrated good internal consistency, test-retest reliability, and convergent validity with other measures of posttraumatic cognitions.	From pre-treatment (1 week before the start of group) to one-month follow-up at about 4 months
Borderline Symptom List- Short Version (BSL-23)	The BSL-23 is a 23-item self-report measure that assesses for DSM borderline personality disorder symptomatology as well as associated problems such as self-criticism, loneliness, helplessness, and problems with trust. The BSL-23 has demonstrated high internal consistency and test-retest reliability, and strong convergent validity with correlations with depression and general psychopathology severity.	From pre-treatment (1 week before the start of group) to one-month follow-up at about 4 months
Borderline Symptom List Behaviour Supplement	The BSL-23 Behaviour Supplement is an 11-item supplemental measure used to assess frequency of problematic behaviours (e.g., non-suicidal self-injury, suicide attempts, suicidal communication, angry outbursts, misuse of substances, etc.) associated with borderline personality disorder.	From pre-treatment (1 week before the start of group) to one-month follow-up at about 4 months
Toronto Alexithymia Scale-20 (TAS-20)	The TAS-20 is a 20-item self-report measure assessing for alexithymia (i.e., issues in identifying and processing emotions) across three factors: difficulty identifying feelings, difficulty describing feelings, and externally-oriented thinking. The TAS-20 has demonstrated adequate levels of convergent validity, good internal consistency, and good test-retest reliability.	From pre-treatment (1 week before the start of group) to one-month follow-up at about 4 months
Experience of Shame Scale (ESS)	The ESS is a 25-item self-report measure assessing characterological shame (e.g., shame of personal habits or personal ability), behavioural shame (e.g., shame in doing or saying something wrong), and bodily shame (e.g., shame regarding one's body). The ESS has demonstrated good internal consistency and test-retest reliability.	From pre-treatment (1 week before the start of group) to one-month follow-up at about 4 months
Difficulties in Emotion Regulation Scale (DERS)	The DERS is a widely used 36-item self-report measure assessing six dimensions of emotion regulation difficulties. The DERS demonstrates good internal consistency, convergent validity, and predictive validity of behaviours reflective of emotion regulation difficulties.	From pre-treatment (1 week before the start of group) to one-month follow-up at about 4 months
Group Cohesion Scale - Revised (GCS-R)	The GCS-R is a self-report measure that measure's group member's perception of their group and the strength of the bonds formed. The GCS-R showed high reliability for use in research and is sensitive to detecting changes in cohesiveness as a function of group development.	Mid treatment (at about 5 weeks after start of group) and post treatment (at about 10 weeks)

Collaborators and Investigators

• Sponsor: St. Joseph's Healthcare Hamilton

Publications and helpful links

General Publications

• Bagby RM, Taylor GJ, Parker JD. The Twenty-item Toronto Alexithymia Scale--II. Convergent, discriminant, and concurrent validity. J Psychosom Res. 1994 Jan;38(1):33-40. doi: 10.1016/0022-3999(94)90006-x.
• Gratz, K. L., & Roemer, L. (2004). Multidimensional assessment of emotion regulation and dysregulation: Development, factor structure, and initial validation of the difficulties in emotion regulation scale. Journal of Psychopathology and Behavioral Assessment, 26, 41-54.
• Foa, E.B., Ehlers, A., Clark, D.M., Tolin, D.F., & Orsillo, S.M. (1999). The Posttraumatic Cognitions Inventory (PTCI): Development and validation. Psychological Assessment, 11(3), 303-314.
• Treadwell, T., Lavertue, N., Kumar, V. K., & Veeraraghavan, V. (2001). The Group Cohesion Scale-Revised: Reliability and validity. International Journal of Action Methods: Psychodrama, Skill Training, and Role Playing, 54(1), 3-12.
• Andrews B, Qian M, Valentine JD. Predicting depressive symptoms with a new measure of shame: The Experience of Shame Scale. Br J Clin Psychol. 2002 Mar;41(Pt 1):29-42. doi: 10.1348/014466502163778.
• Bohus M, Kleindienst N, Limberger MF, Stieglitz RD, Domsalla M, Chapman AL, Steil R, Philipsen A, Wolf M. The short version of the Borderline Symptom List (BSL-23): development and initial data on psychometric properties. Psychopathology. 2009;42(1):32-9. doi: 10.1159/000173701. Epub 2008 Nov 20.

Study record dates

Study Major Dates

• Study Start (Estimated): June 1, 2026
• Primary Completion (Estimated): June 1, 2028
• Study Completion (Estimated): December 1, 2028

Study Registration Dates

• First Submitted: April 20, 2026
• First Submitted That Met QC Criteria: May 4, 2026
• First Posted (Actual): May 8, 2026

Study Record Updates

• Last Update Posted (Actual): May 8, 2026
• Last Update Submitted That Met QC Criteria: May 4, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: borderline personality disorder; virtual; posttraumatic stress disorder; group therapy; written exposure therapy
• Additional Relevant MeSH Terms: Trauma and Stressor Related Disorders; Mental Disorders; Personality Disorders; Stress Disorders, Traumatic; Stress Disorders, Post-Traumatic; Borderline Personality Disorder
• Other Study ID Numbers: 18906

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No