The Development and Evaluation of a Brief CFT Intervention for Trauma

The project will implement a five-minute daily self-practice CFT intervention and evaluate its impact on psychological and physiological factors associated with trauma. It aims to offer a novel intervention which may facilitate further benefits from trauma-specific therapy. Follow-up data may demonstrate maintenance of positive effects and increased positive effects if self-practice is continued. This would be a unique use of self-practice CFT specifically for trauma clients.

Study Design The study will use a delayed intervention Randomised Controlled Trial (RCT) using a block design.A delayed intervention group will act as a passive control group. Participants will engage in a daily five-minute self-practice CFT intervention prior to engaging in trauma-specific TAU. The CFT intervention will be adapted specifically for trauma clients based on the literature review, involvement of service users, and close collaboration with Professor Paul Gilbert. The project will involve three stages, outlined below.

Stage One: Development of CFT intervention and feasibility testing

Development The final version of the adapted five-minute CFT practice will include consultation with Paul Gilbert as original author of the five-minute CFT intervention (unpublished) as well as consultation with research supervisors. It will be available in both audio and written format. Permission has kindly been given by Paul Gilbert to adapt this for use in the project.

The current version of the CFT intervention includes: instructions, an explanation of compassion and aims of the intervention. It includes several exercises designed to increase self-compassion including breathing exercises and compassionate imagery exercises focused on self and others.

Throughout the adaptation process, services users' ideas will be considered. The intervention will include explicit instructions not to focus on traumatic events participants have experienced. This will be addressed in their trauma-specific therapy . Participants will be encouraged to focus on milder difficulties and stressors. The adaptations will account for the current literature in CFT and maintain its basic principles, focusing on building self-compassion and reducing self-criticism.

Participant sampling for feasibility testing will be opportunistic, seeking voluntary engagement from clients currently accessing services. The sample size for this stage is not explicitly defined and will depend on the number of interested parties. This aims to test feasibility and acceptability of the intervention and its instructions with a clinical population. Participants will be asked to practice the intervention over a two-week period.

Stage Two: Randomised controlled trial Design The research will utilise a single-blind blocked-randomisation design, incorporating three-week intervention versus waiting-list blocks. Following the end of the initial block, participants who formed the passive, waiting-list group will engage in the active intervention, whilst the active group will continue to remain on the waiting list. Both routine and project-specific outcomes measures will be implemented.

Therapists from the recruitment site will conduct screening assessments and post TAU assessments. All other measurements will be completed with the primary researcher. Prospective participants will be provided with an information sheet as part of the screening interview and, if they consent, will be contacted by the researcher. They will be given the opportunity to ask questions and be asked to sign a consent form if they wish to participate. It will be made clear that non-participation will have no adverse effects on their access to psychological treatment and that engaging in the project will not affect their access to treatment. An initial appointment will then be made and the pre-intervention assessments completed. Participants will be allocated to the CFT or waiting-list condition using blocked randomisation. Self-report measures will be uploaded to an academically-focused online survey tool (eSurv) and participants will have Heart Rate Variability (HRV) measurements taken during face-to-face appointments with the primary researcher.

The five-minute CFT self-practice intervention will be available both in written and audio (CD and mp3) formats. Participants will receive a daily email or text reminder to practice the intervention if deemed appropriate. Participants will be given the choice to complete a daily monitoring sheet or have their daily online access monitored to record levels of CFT practice. Participants will be asked to practice the intervention on a daily basis for three weeks with repeated completion of the online assessments and the HRV measurements in the week following the block.

An a priori power calculation was obtained using G*Power 3.1.9 software (Faul, Erdfelder, Buchner \& Lang, 2009). With the Depression, Anxiety and Stress Scale (DASS-21: Lovibond \& Lovibond, 1995) as the primary outcome measure, the average effect size of a brief CFT intervention on the DASS was equivalent to a large effect size f of .74 (McEwan \& Gilbert, 2013). An average estimate of test-retest reliability is 0.77 (Brown, Chorpita, Korotitsch \& Barlow, 1997).

Given the number of groups (2) and repetitions (4) in the planned study and assuming a test-retest reliability of .77, a sample size of at least 16 (8 per group) will be required to provide sufficient power (80%) to detect an effect of similar magnitude (f = .74) at an alpha level of .05.

Average attrition rates for clients with PTSD are approximately 20%, although rates vary up to 48% (Imel, Laska, Jakupcak \& Simpson, 2013). A cautious 60% (approx.) attrition rate has been considered given the research is additional to participants' involvement at the CTRG. Further allowing room for a more moderate effect size, given that the intervention has not previously been trialled with a clinical sample, a target sample of 40 participants will be sought. Given the 150 referrals received by the CTRG last year this is feasible.

Withdrawal Participants will be assigned a code number with which all of their assessment data will be stored on a password-protected computer file. This will be accessible only to the researcher and any transferring of data will be done using an encrypted memory stick. Any personal data used to contact participants will be deleted upon completion of the experimental aspects of the project. Participants can withdraw at any time but will be informed that any data collected past the first week of the intervention process cannot be erased and may still be used in the project analyses. Consent forms will be signed and will be stored in a locked filing cabinet at the researcher's home office and transferred to the University of Lincoln's archived storage following project completion. Data will be stored for seven years in line with the University's data storage policy.

Implications and Dissemination This research project will contribute to the theoretical literature on both CFT and PTSD. It is anticipated that it will offer new findings regarding self-practice interventions for PTSD which may have beneficial psychological and physiological implications and impact on TAU outcomes. The project will be prepared for publication in an appropriate peer-reviewed journal and presented at relevant conferences. It may also be disseminated on the Compassion Mind Foundation Website.

In the event that any participants find the intervention difficult or experience distress, they will be able to discuss this with an identified person and if deemed appropriate, will be withdrawn from the project. Research suggests continued practice may reduce fear of compassion (Rockliff, et al. 2008) and this information will be shared with participants. It is felt that the risk of such adverse events is minimal.