Treatment of multiple traumatized adolescents by enhancing regulation skills and reducing trauma related symptoms: rationale, study design, and methods of randomized controlled trial (the Mars-study).

Background: There is ongoing debate regarding the treatment of severe and multiple traumatized children and adolescents with post-traumatic stress disorder (PTSD). Many clinicians favor a phase-based treatment approach (i.e., a stabilization phase prior to trauma-focused therapy) over immediate trauma-focused psychological treatment, despite the lack of scientific evidence. Research on the effects of different treatment approaches is needed for children and adolescents with (symptoms of complex) PTSD resulting from repeated sexual and/or physical abuse during childhood.

Objective: This paper describes the rationale, study design, and methods of the MARS-study, a two-arm randomized controlled trial (RCT) that aims to compare the results of phase-based treatment with those of immediate trauma-focused treatment and determine whether immediate trauma-focused treatment is not worse than phase-based treatment in reducing PTSD symptoms.

Methods: Participants are individuals between 12 and 18 years who meet the diagnostic criteria for PTSD due to repeated sexual abuse, physical abuse, or domestic violence during childhood. Participants will be blindly allocated to either the phase-based or immediate trauma-focused treatment condition. In the phase-based treatment condition, participants receive 12 sessions of the Dutch version of Skill Training in Affective and Interpersonal Regulation (STAIR-A), followed by 12 sessions of EMDR therapy. In the immediate trauma-focused condition, the participants receive 12 sessions of EMDR therapy. The two groups are compared for several outcome variables before treatment, mid-treatment (only in the phase-based treatment condition), after 12 trauma-focused treatment sessions (post-treatment), and six months post-treatment (follow-up). The main parameter is the presence and severity of PTSD symptoms (Clinician-Administered PTSD Scale for Children and Adolescents, CAPS-CA). The secondary outcome variables are the severity of complex PTSD symptoms (Interpersonal Problems as measured by the Experiences in Close Relationship-Revised, ECR-RC; Emotion Regulation as measured by the Difficulties in Emotion Regulation Scale, DERS; Self Esteem as measured by the Rosenberg Self Esteem Scale, RSES), changes in anxiety and mood symptoms (Revised Anxiety and Depression Scale; RCADS), changes in posttraumatic cognitions (Child Posttraumatic Cognitions Inventory, CPTCI), changes in general psychopathology symptoms (Child Behavior Checklist, CBCL), and Quality of Life (Youth Outcome Questionnaire, Y-OQ-30). Furthermore, parental stress (Opvoedingsvragenlijst, OBVL) and patient-therapist relationship (Feedback Informed Treatment, FIT) will be measured, whereas PTSD symptoms will be monitored in each session during both treatment conditions (Children's Revised Impact of Event Scale, CRIES-13).

Discussion: Treating (symptoms of complex) PTSD in children and adolescents with a history of repeated sexual and/or physical abuse during childhood is of great importance. However, there is a lack of consensus among trauma experts regarding the optimal treatment approach. The results of the current study may have important implications for selecting effective treatment options for clinicians working with children and adolescents who experience the effects of exposure to multiple interpersonal traumatic events during childhood.

Trial Registrations: The study was registered on the "National Trial Register (NTR)" with the number NTR7024. This registry was obtained from the International Clinical Trial Registry Platform (ICTRP) and can be accessed through the ICTRP Search Portal ( https://trialsearch.who.int/ ).