The effectiveness of eye movement desensitization and reprocessing (EMDR) 2.0 and the Flash technique with post-traumatic stress disorder (PTSD) patients

INTERVENTION: Participants are randomly assigned to one of three treatment conditions using an online tool (sealedenvelope.com). There are two intervention groups and one control group. Participants in one intervention group will receive EMDR 2.0 therapy and participants in the other intervention group will receive the Flash technique. Participants in the control group will receive standard EMDR therapy. All conditions will consist of si Xweekly sessions, with a duration of 60 minutes. Follow up lasts 12 weeks. CONDITION: Treatment of (complex) PTSD symptoms in patients diagnosed with PTSD. ; Mental and Behavioural Disorders ; Post‐traumatic stress disorder PRIMARY OUTCOME: ; 1. PTSD symptoms measured with the Clinician‐Administered PTSD Scale for DSM‐5 (CAPS‐5) at baseline, post‐treatment (4 weeks after the last treatment session) and follow‐up (12 weeks after the last treamtent session) and the PTSD symptom Checklist for DSM‐5 (PCL‐5) at baseline, weekly during treatment phase and bi‐weekly after the last treatment session until 12 week follow‐up.; 2. PTSD diagnosis measured with the CAPS‐5 at baseline, post‐treatment and follow‐up.; 3. Complex PTSD symptoms measured with the International Trauma Questionnaire (ITQ) at baseline, post‐treatment and follow‐up.; 4. Complex PTSD diagnosis measured with the ITQ at baseline, post‐treatment and follow‐up.; SECONDARY OUTCOME: ; 1. Depressive symptoms measured with the Beck Depression Inventory‐II (BDI‐II) at baseline, weekly during the treatment phase and bi‐weekly after the last treatment session until 12‐week follow‐up.; 2. Dissociative symptoms measured with the Dissociative Experiences Scale (DES) at baseline, post‐treatment and follow‐up.; 3. General psychiatric symptoms measured with the Brief Symptom Inventory (BSI) at baseline, weekly during the treatment phase and bi‐weekly after the last treatment session until 12‐week follow‐up.; 4. Experiential avoidance measured with the Acceptance and Action Questionnaire‐II (AAQ‐II) at baseline, weekly during the treatment phase and bi‐weekly after the last treatment session until 12‐week follow‐up.; 5. Treatment acceptability measured with four questions that measure several facets which could be grouped under treatment acceptability at the second week of treatment and two weeks after the last treatment session.; 6. Treatment efficiency measured with intervention time needed to achieve a Subjective Units of Disturbance (SUD) score of 0 and amount of sessions needed to achieve clinically significant change and a cut‐off score on the PCL‐5. Intervention time and SUD scores will be measured at treatment sessions and the PCL‐5 will be measured weekly during the treatment phase.; INCLUSION CRITERIA: 1. A primary diagnosis of PTSD, administered with the CAPS‐5. 2. A minimum age of 18 years old. 3. An estimated IQ of above 80. 4. Sufficient understanding of the Dutch language.