Core belief inclusive protocol in NHS Talking Therapies: helping obsessive compulsive disorder
| ISRCTN | ISRCTN81900834 |
|---|---|
| DOI | https://doi.org/10.1186/ISRCTN81900834 |
| Integrated Research Application System (IRAS) | 341182 |
| Cambridgeshire and Peterborough NHS Foundation Trust Research and Development Department local reference number | M001155 |
| Sponsor | Anglia Ruskin University |
| Funders | Investigator initiated and funded, National Institute for Health and Care Research |
- Submission date
- 01/04/2026
- Registration date
- 01/04/2026
- Last edited
- 01/04/2026
- Recruitment status
- Recruiting
- Overall study status
- Ongoing
- Condition category
- Mental and Behavioural Disorders
Plain English summary of protocol
Background and study aims
Obsessive-Compulsive Disorder (OCD) is a common mental health difficulty that can significantly affect daily life. Current psychological treatment within NHS Talking Therapies usually involves cognitive behavioural therapy (CBT), which helps individuals gradually face feared situations and reduce compulsive behaviours.
Research suggests that focusing more directly on a person’s core self-beliefs (deeply held beliefs about the self) may improve therapy outcomes for some individuals. However, current OCD treatments do not consistently include structured techniques specifically targeting core self-beliefs.
This study aims to investigate whether an enhanced CBT approach that explicitly addresses self-based core beliefs can be delivered within NHS Talking Therapies and whether it shows potential to improve treatment outcomes. The study also evaluates whether the enhanced approach is acceptable to both participants and therapists.
This is a feasibility study, meaning the main aim is to determine whether the enhanced treatment can be delivered successfully in routine NHS services and whether it shows promise for future research.
Who can participate?
Adults aged 18 to 65 who are receiving treatment for Obsessive-Compulsive Disorder through NHS Talking Therapies.
What does the study involve?
Participants are randomly allocated (by computer) to one of three groups:
A) Waiting list group (participants wait a short period before receiving treatment as usual)
B) Treatment as usual (standard CBT provided within NHS Talking Therapies)
C) Augmented CBT including additional techniques focusing on core self-beliefs
Participants in the two therapy groups attend approximately twelve weekly therapy sessions, each lasting around 60 minutes, followed by a follow-up appointment. The waiting list group waits for a shorter period than typical NHS waiting times before beginning treatment outside of the study.
Participants complete questionnaires at several time points during therapy and at follow-up. Some of these questionnaires are routinely used in NHS Talking Therapies, while others are included for research purposes. Participants may also be invited to provide feedback about their experience of therapy.
The information collected helps researchers understand whether the enhanced treatment can be delivered successfully and whether it may improve treatment outcomes for OCD.
What are the possible benefits and risks of participating?
Participants may benefit from receiving psychological therapy for OCD. The augmented therapy may help improve understanding of self-beliefs that contribute to OCD symptoms. However, improvement cannot be guaranteed.
As with all psychological therapies, discussing personal experiences and confronting feared situations may sometimes lead to temporary emotional discomfort. This level of discomfort is expected to be similar to standard psychological treatment. Therapists monitor wellbeing throughout therapy and provide support where needed.
Taking part in the study helps researchers improve understanding of OCD treatment and may contribute to improving future NHS psychological therapies.
Where is the study run from?
The study is conducted within NHS Cambridgeshire and Peterborough NHS Foundation Trust (CPFT) Talking Therapies services in collaboration with Anglia Ruskin University.
When is the study starting and how long is it expected to run for?
Recruitment is expected to begin in Spring 2026. Participation lasts for the duration of therapy (approximately 12 sessions) and includes a follow-up appointment approximately 6 months after treatment.
The overall study is expected to run for the duration of the doctoral research project, until March 2028.
Who is funding the study?
The study forms part of a PhD research project sponsored by Anglia Ruskin University.
Who is the main contact?
Chief Investigator: Laura Laken, lcl121@pgr.aru.ac.uk (Laura Laken)
Contact information
Principal investigator, Scientific, Public
Anglia Ruskin University
East Road
Cambridge
CB1 1PT
United Kingdom
 ORCID ID |
0009-0004-7801-7387 |
|---|---|
| Phone | +44 07875515835 |
| LCL121@pgr.aru.ac.uk |
Study information
| Primary study design | Interventional |
|---|---|
| Allocation | Randomized controlled trial |
| Masking | Open (masking not used) |
| Control | Dose comparison |
| Assignment | Parallel |
| Purpose | Health services research, Treatment |
| Scientific title | Core belief–inclusive cognitive behavioural protocol versus treatment as usual for obsessive–compulsive disorder in NHS Talking Therapies: a feasibility study |
| Study objectives | Applied with CONSORT guidelines: Primary Objective To evaluate the feasibility and acceptability of delivering a core belief–involved cognitive behavioural therapy (CBT) augmentation for adults experiencing Obsessive-Compulsive Disorder (OCD) within NHS Talking Therapies services. Feasibility will be assessed through recruitment rates from routine service pathways, participant retention across treatment and follow-up timepoints, treatment adherence and session attendance, therapist protocol fidelity, therapist-reported confidence, usability, and perceived clinical coherence of the intervention, and participant-reported acceptability, engagement, and perceived relevance of treatment. Feasibility hypotheses The CBT augmentation will demonstrate acceptable feasibility within NHS Talking Therapies, indicated by recruitment, retention, adherence, and fidelity parameters comparable to treatment as usual. Therapists delivering the augmented CBT protocol will report acceptable levels of confidence, usability, and perceived clinical coherence, indicating that the intervention can be implemented within routine clinical practice. Secondary Objective To obtain preliminary estimates of change in OCD symptom severity across treatment conditions in order to inform the design of a full powered future trial . Clinical hypotheses Participants receiving augmented CBT will show greater reductions in OCD symptom severity from baseline to post-treatment and follow-up compared with participants allocated to the waiting-list arm. There will be a difference in OCD symptom change between participants receiving augmented CBT and those receiving treatment as usual. Exploration Objectives (Mechanisms of Change) To explore whether changes in self-based core belief process are associated with changes in OCD symptom severity across the course of therapy. Mechanism hypotheses Participants receiving augmented CBT will show greater reductions in negative self-based core beliefs compared with participants receiving treatment as usual. Participants receiving augmented CBT will show greater reductions in self-ambivalence compared with participants receiving treatment as usual. Reductions in negative self-based core beliefs will be associated with reductions in OCD symptom severity across the treatment period. Acceptability and Engagement Objectives To evaluate participant engagement with the intervention and perceived relevance of the therapeutic approach. Acceptability hypotheses Participants allocated to the augmented CBT condition will demonstrate withdrawal rates comparable to or lower than those in the treatment as usual group. Participants receiving augmented CBT will report acceptable levels of engagement and perceived relevance of treatment, as reflected in post-treatment feedback and sessional measures. |
| Ethics approval(s) |
Approved 06/03/2026, North West - Greater Manchester Central Research Ethics Committee (2 Redman Place, Stratford, London, E20 1JQ, United Kingdom; +44 0207 104 8000; gmcentral.rec@hra.nhs.uk), ref: - |
| Health condition(s) or problem(s) studied | Obsessive-Compulsive Disorder (OCD) in adults receiving psychological treatment within NHS Talking Therapies services. |
| Intervention | Participants are randomly allocated to one of three study arms: Waiting list control (A) Participants allocated to the waiting list receive no active psychological treatment for Obsessive-Compulsive Disorder during the waiting period but continue to have access to usual service support. Participants are offered treatment following completion of the waiting period in accordance with NHS Talking Therapies procedures. Treatment as usual (B) Participants receive standard exposure response prevention CBT for Obsessive-Compulsive Disorder as delivered within NHS Talking Therapies services. Treatment is delivered by qualified therapists following routine service protocols of 12 sessions, typically involving weekly individual therapy sessions. Arm C: Core belief–involved CBT (augmented intervention) Arm C retains a fundamental CBT approach with the mentioned psychometrics, same mode, frequency, duration of contact and episode. However, the difference between B and C will be the psychological application of cognitive therapy and techniques directly including core beliefs within and between all sessions. This will involve early identification of an unhealthy and a healthier alternative core belief, connection to historical predisposing and perpetuating factors, psychoeducation on core beliefs, and core belief modification interventions within and between sessions. Therapy is delivered individually by trained NHS Talking Therapies clinicians across twelve sessions, followed by a follow-up appointment (for arm B and C). Participants complete outcome measures at multiple time points across the treatment period to evaluate feasibility of repeated measurement and preliminary clinical indicators. Participants are randomly allocated to study arms using computer-generated randomisation procedures. The target sample size (n=131) was granted in the ethics approval. The sample size selected allows estimation of feasibility parameters (recruitment, retention, adherence) and provides preliminary estimates of effect size to inform a future fully powered trial. It also allows for expected attrition across repeated measurement time points. |
| Intervention type | Behavioural |
| Primary outcome measure(s) |
|
| Key secondary outcome measure(s) |
|
| Completion date | 31/03/2028 |
Eligibility
| Participant type(s) | |
|---|---|
| Age group | Mixed |
| Lower age limit | 18 Years |
| Upper age limit | 65 Years |
| Sex | All |
| Target sample size at registration | 131 |
| Key inclusion criteria | 1. Completed referral and assessment from NHS Talking Therapies and indicated ‘Yes’ to contact for research participation. 2. OCD working diagnosis confirmed via structured clinical assessment routinely used within NHS Talking Therapies. 3. All participants must be aged 18 to 65 specifically experiencing symptoms and goals indicating Obsessive Compulsive Disorder requiring treatment with a Therapist. 4. Any prescribed medication is GP concordant and has been stable for three months, to control for psychopharmacological effects. 4. Amenable to either webcam or in-person treatment. 5. To attend individual therapy sessions at a reasonable and regular frequency e.g., weekly. 6. To complete therapy in English without the aid of translation services. 7. Comorbid affective disorders e.g., major depressive disorder, are secondary to OCD. OCD to be the clear dominant pathology and the reason for seeking treatment. |
| Key exclusion criteria | 1. Individuals not meeting NHS Talking Therapies suitability criteria for outpatient psychological therapy. 2. Awaiting diagnosis of learning disability. 3. Current or pending diagnosis of neurodevelopmental condition e.g., ADHD, where treatment adaptation would be required beyond the scope of the study protocol. 4. Current significant alcohol or drug misuse. 5. Simultaneously being under the care of other mental health services or on waiting list for alternative psychotherapeutic service. |
| Date of first enrolment | 30/04/2026 |
| Date of final enrolment | 31/12/2027 |
Locations
Countries of recruitment
- United Kingdom
- England
Study participating centre
Cambridge Road
Fulbourn
Cambridge
CB21 5EF
England
Results and Publications
| Individual participant data (IPD) Intention to share | No |
|---|
Editorial Notes
01/04/2026: Study’s existence confirmed by the Cambridgeshire and Peterborough NHS Foundation Trust, UK.
