Cognitive behaviour therapy for depersonalisation-derealisation disorder

Cognitive behaviour therapy for depersonalisation-derealisation disorder (CBT-f-DDD): a feasibility study

Status

Active, not recruiting

Phases

Unknown

Study type

Interventional

Source

ISRCTN

Registry ID

ISRCTN97686121

Enrollment

Registered

2023-01-05

Start date

2022-05-13

Completion date

Unknown

Last updated

2026-01-12

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Depersonalisation-Derealisation Disorder (DDD) Mental and Behavioural Disorders

Interventions

Participants with symptoms meeting the clinical threshold for Depersonalisation-Derealisation Disorder (DDD) who consent to enter the study will be randomly allocated to either the Cognitive Behaviour

Eligibility

Sex/Gender

All

Age

16 Years to 75 Years

Inclusion criteria

Inclusion criteria: 1. Aged 16-75 years 2. Have current symptoms of DDD meeting Diagnostic and Statistical Manual of Mental Disorders (DSM-5) diagnostic criteria

Exclusion criteria

Exclusion criteria: 1. People having previously had CBT specifically for DDD 2. Where there are co-morbid current diagnoses of: 2.1. Psychosis spectrum disorder 2.2. Substance dependence 2.3. Intellectual disability 2.4. Cognitive impairment due to head injury or organic disorder 2.5. Post-traumatic stress disorder (PTSD) 3. Participants lacking the capacity to consent to take part in the study 4. Insufficient proficiency in the English language to engage in CBT 5. Requiring special communication needs arrangements. 6. People who are not registered with a GP 7. Those with depersonalisation and/or derealisation symptoms which score below clinical severity (i.e., a total score of 0-2) in response to the diagnostic questions 8. Participants involved in other research studies involving mental or physical health research (including drug trials)

Design outcomes

Primary

Measure	Time frame
The primary outcomes relate to the feasibility and acceptability measures (see below). The researchers will use a traffic light system to establish the success of the trial based on each measure. 1. Recruitment/eligibility data: collected throughout the recruitment period (6-month window, includes Time 0 and Time 1) 2. Participant attrition rates: collected throughout participant journey (12 months), and reviewed at each timepoint (Time 0-3) 3. Therapist attrition rates and reasons for withdrawing throughout the study: collected throughout the recruitment and intervention period (Time 0-2) 4. Resources needed to complete CBT-f-DDD: 4.1. Length of time required for RAs to complete assessments and collect and analyse data (from research assistant time sheets - collected at each time point, Time 0-3, throughout the study), CBT attendance rates (from electronic patient records - Time 1-2), and the amount and nature of supervision required (from Co-PI supervision notes - Time 1-2) 4.2. A minimum of 12 sessions and a maximum of 24 weekly sessions are established for the 6- month window, allowing for 50% attendance rates (Time 1-2, 6 months) 5. Therapist adherence to CBT-f-DDD (fidelity) (Time 1-2): Records of session content, participants’ engagement with CBT-f-DDD, and homework tasks completed (all from therapist post-session checklists). A random sample of 10% of audio-recorded therapy sessions will be evaluated using standardised CBT protocols for adherence to the CBT model as well as an adapted CBT-f-DDD checklist 6. Participant acceptability (Time 2 and 3): 6.1. Acceptability of assessment procedures and measures (Time 2 and 3) 6.2. Acceptability of CBT-f-DDD including aspects of the treatment found helpful and unhelpful, perceived impact of the intervention, and satisfaction with the intervention and therapists (from thematic analysis of the qualitative interviews [Time 3]; and as measured by items on the end-of-treatment questionnaire “CBT-f-DDD brief outcome	—

Measure

Time frame

The primary outcomes relate to the feasibility and acceptability measures (see below). The researchers will use a traffic light system to establish the success of the trial based on each measure. 1. Recruitment/eligibility data: collected throughout the recruitment period (6-month window, includes Time 0 and Time 1) 2. Participant attrition rates: collected throughout participant journey (12 months), and reviewed at each timepoint (Time 0-3) 3. Therapist attrition rates and reasons for withdrawing throughout the study: collected throughout the recruitment and intervention period (Time 0-2) 4. Resources needed to complete CBT-f-DDD: 4.1. Length of time required for RAs to complete assessments and collect and analyse data (from research assistant time sheets - collected at each time point, Time 0-3, throughout the study), CBT attendance rates (from electronic patient records - Time 1-2), and the amount and nature of supervision required (from Co-PI supervision notes - Time 1-2) 4.2. A minimum of 12 sessions and a maximum of 24 weekly sessions are established for the 6- month window, allowing for 50% attendance rates (Time 1-2, 6 months) 5. Therapist adherence to CBT-f-DDD (fidelity) (Time 1-2): Records of session content, participants’ engagement with CBT-f-DDD, and homework tasks completed (all from therapist post-session checklists). A random sample of 10% of audio-recorded therapy sessions will be evaluated using standardised CBT protocols for adherence to the CBT model as well as an adapted CBT-f-DDD checklist 6. Participant acceptability (Time 2 and 3): 6.1. Acceptability of assessment procedures and measures (Time 2 and 3) 6.2. Acceptability of CBT-f-DDD including aspects of the treatment found helpful and unhelpful, perceived impact of the intervention, and satisfaction with the intervention and therapists (from thematic analysis of the qualitative interviews [Time 3]; and as measured by items on the end-of-treatment questionnaire “CBT-f-DDD brief outcome

—

Secondary

Measure	Time frame
1. Health data and demographics: Health economic outcomes measured using the Client Service Receipt Inventory (CSRI) at Time 0, 2 and 3 2. Clinical data: 2.1. Depersonalisation-Derealisation Disorder measured using the Cambridge Depersonalization Scale (CDS) at Time 0-3 2.2. Dissociation measured using the Dissociative Experiences Scale (DES) at Time 0-3 2.3. Depression measured using Patient Health Questionnaire (PHQ)-9 at Time 0-3 2.4. Anxiety measured using Generalised Anxiety Disorder Assessment (GAD-7) at Time 0-3 2.5. Co-morbidity measured using Clinical Interview Schedule - Revised (CIS-R) at Time 0 and 3 2.6. Functioning measured using the Work and Social Adjustment scale (WASA) at Time 0-3 2.7. Global rating of change question (i.e., “do you feel better?”) at Time 2 2.8. Quality of life measured using EQ-5D-5L at Time 0, 2 and 3 2.9. Clinical characteristics including the age of onset of DDD, duration, co-morbid diagnoses, previous treatments for DDD, type and dosage of current medication; measured using semi-structured interview of DDD experiences (Time 0-3) and CSRI (Time 0, 2 and 3)	—

Measure

Time frame

1. Health data and demographics: Health economic outcomes measured using the Client Service Receipt Inventory (CSRI) at Time 0, 2 and 3 2. Clinical data: 2.1. Depersonalisation-Derealisation Disorder measured using the Cambridge Depersonalization Scale (CDS) at Time 0-3 2.2. Dissociation measured using the Dissociative Experiences Scale (DES) at Time 0-3 2.3. Depression measured using Patient Health Questionnaire (PHQ)-9 at Time 0-3 2.4. Anxiety measured using Generalised Anxiety Disorder Assessment (GAD-7) at Time 0-3 2.5. Co-morbidity measured using Clinical Interview Schedule - Revised (CIS-R) at Time 0 and 3 2.6. Functioning measured using the Work and Social Adjustment scale (WASA) at Time 0-3 2.7. Global rating of change question (i.e., “do you feel better?”) at Time 2 2.8. Quality of life measured using EQ-5D-5L at Time 0, 2 and 3 2.9. Clinical characteristics including the age of onset of DDD, duration, co-morbid diagnoses, previous treatments for DDD, type and dosage of current medication; measured using semi-structured interview of DDD experiences (Time 0-3) and CSRI (Time 0, 2 and 3)

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Countries

England, United Kingdom

Outcome results

None listed

Source: ISRCTN (via WHO ICTRP) · Data processed: Feb 5, 2026