Modular Patient Centred CBT (MPC) for Complex PTSD (CPTSD) is a manualized psychotherapy programme that consists of five treatment modules addressing 1) Affect dysregulation, 2) Disturbed relationships, 3) Negative self-concept, 4) PTSD symptoms and 5) Insomnia and trauma-related nightmares.

This aim of this first pilot randomised controlled trial (RCT) is to increase chances of a future successful efficacy RCT (Phase III trial) comparing the efficacy (on symptoms of CPTSD and co-morbid disorders) of a flexible, patient-centred version of the MPC treatment programme (where the client actively participates in treatment decisions) with a control treatment, where the five treatment modules are delivered in a predefined order.

The primary objective of the pilot study is to:

1. Assess the implementation of the trial process in terms of inclusion, implementation and data collection
2. Assess necessary resources, including the use of tablets for data collection, time spent on the project by participating therapists, assessing psychologists and secretaries

The secondary objective is to:

1. Assess changes in symptoms of CPTSD between the intervention and control group as well as within each group
2. Examine changes in levels of comorbidity associated with CPTSD, such as anxiety, depression, insomnia, somatic complaints, drugs and alcohol intake between the intervention and control group as well as within each group
3. Examine changes in well-being, functioning and attachment style between the intervention and control group as well as within each group
4. Examine developments in client motivation and working alliance between the intervention and control group as well as within each group.

60 veterans with CPTSD are randomised to receive either the flexible, patient-centred version of the MPC treatment programme or the control treatment.

The investigators will consider the study as complete if the following success criteria are met:

1. > 70% of potential participants accept and be included in the study
2. Completion rate of 70%, that is, the investigators expect to have complete end-of-treatment data of at least 70% of all participants included
3. Complete three-month follow-up of at least 50% of all participants included.

The project neither collects new biological material nor biological material from existing biobanks. The project is based on questionnaire data.

ICD-11 complex PTSD (CPTSD) is a new diagnosis and up to this date, no effective treatment has been identified to help clients with this severe mental disorder. Therefore, it is very important that effective treatment methods for clients with CPTSD be identified.

In 2019 the Danish Veteran Centre launched the development of a treatment programme for veterans with CPTSD; Modular Patient Centred CBT (MPC) for CPTSD. MPC is a manualised treatment programme that consists of 32 individual psychotherapy sessions, divided into an initial treatment module (two therapy sessions) and five treatment modules (each consisting of six therapy sessions) that can be combined in different ways to adapt to each client's most prominent symptoms, preferences and readiness (to work with exposure, for instance). The five treatment modules address 1) Affect dysregulation (6 sessions), 2) Disturbed relationships (6 sessions), 3) Negative self-concept (6 sessions), 4) PTSD symptoms (6 sessions) and 5) Insomnia and trauma-related nightmares (6 sessions).

This first trial of the MPC treatment programme is conducted as a pilot randomised controlled trial. The primary objective of this study is to increase chances of a future successful efficacy RCT (Phase III trial) comparing the efficacy (on symptoms of CPTSD and co-morbid disorders) of a flexible, patient-centred version of the MPC treatment programme (where the client actively participates in treatment decisions) with a control treatment, where the five treatment modules are delivered in a predefined order; 1) Affect dysregulation, 2) Disturbed relationships, 3) Negative self-concept, 4) PTSD symptoms, and 5) Insomnia and trauma-related nightmares.

The primary objective of the pilot study is to:

1. Assess the implementation of the trial process in terms of inclusion, implementation and data collection
2. Assess necessary resources, including the use of tablets for data collection, time spent on the project by participating therapists, assessing psychologists and secretaries

The secondary objective is to:

1. Assess changes in symptoms of CPTSD, assessed with the International Trauma Questionnaire (ITQ; Cloitre et al., 2018) between the intervention and control group as well as within each group
2. Examine changes in levels of comorbidity associated with CPTSD, such as anxiety, depression, insomnia, somatic complaints, drugs and alcohol intake between the intervention and control group as well as within each group
3. Examine changes in well-being, functioning and attachment style between the intervention and control group as well as within each group
4. Examine developments in client motivation and working alliance between the intervention and control group as well as within each group.

60 veterans with CPTSD are randomised to receive either the flexible, patient-centred version of the MPC treatment programme or the control treatment. As an integral part of the treatment, a short assessment is conducted after each treatment module by having the client complete the primary outcome measure, the ITQ which is used as a measure for assessing ICD-11 PTSD and CPTSD. In practice, the client fills in the ITQ on a tablet in the beginning of the last session of each treatment module, after which the client and therapist receive an automatic response on the tablet, establishing whether the client (based on the ITQ) continues to meet the diagnostic criteria for PTSD or CPTSD. If the client has achieved sufficient symptom recovery and no longer meets the diagnostic criteria for CPTSD, the client is considered a treatment completer. However, the client and the therapist might decide to continue treatment until the client no longer meets the diagnostic criteria for PTSD. In this way, treatment can continue to up till 32 therapy sessions but client and therapist can end the treatment earlier if the client has a valid assessment and falls out of CPTSD criteria.

Since the study is a pilot study, aiming to inform a future RCT, the investigators will consider the study as complete if the following success criteria are met:

1. > 70% of potential participants accept and be included in the study
2. Completion rate of 70%, that is, the investigators expect to have complete data (end-of-treatment outcome assessment completed at the final therapy session) of at least 70% of all participants included
3. Complete three-month follow-up of at least 50% of all participants included.

The treatment is carried out at five local veteran centres in Denmark by clinical psychologists employed by the Military Psychology Department (MPD), Danish Veterans Centre. The participating psychologists receive training and regular method-specific supervision in the MPC treatment programme.

The project neither collects new biological material nor biological material from existing biobanks. The project is based on questionnaire data

Note regarding study objectives, results reporting, and start date (added March 2025):

The original registration emphasized feasibility-related objectives as primary, including aspects of recruitment, implementation, and data collection. Clinical outcomes listed as secondary objectives have also been explored in more depth in the final analyses and will be reported in a forthcoming manuscript.

As this study does not qualify as an Applicable Clinical Trial (ACT) under FDAAA 801, results submission is not required by law. However, results will be submitted voluntarily after acceptance of the primary publication to ensure transparency and consistency with journal embargo policies.

The Study Start Date was also updated to January 5, 2021, to reflect the actual date of first participant enrollment with completed baseline assessment.

Inclusion Criteria:

• Meets the diagnostic criteria for CPTSD, assessed with the ITQ
• Danish veteran (cf. the Veteran Policy of Denmark )
• Seeks help at the Military Psychology Department, Danish Veterans Centre, for deployment-related psychological issues

Exclusion Criteria:

• Severely suicidal
• Current alcohol or drug abuse that prevents treatment
• Blast injuries or current severe attention disorder
• Has received psychotherapeutic treatment in the past three months
• Is participating in another research project that interferes with this study

Due to privacy and data protection regulations of the Danish Defence, data from the current study cannot be shared.