Unfortunately, traumatic experiences in childhood and adolescence are common: a meta-analysis based on 65 international studies indicates that nearly 20% of women and 8% of men experienced sexual abuse prior to the age of 18 . Regarding physical abuse in Western and European nations, numbers range from 3.6% to 16.3% [2–5]. These negative childhood experiences do not only have short-term consequences concerning the victims’ mental health – they are also related to a number of psychiatric disorders during the whole life span . Consequently, people exposed to childhood sexual abuse (CSA) have a 2.4 heightened risk for the development of psychopathology compared to those without such experiences. For childhood physical abuse (CPA), this factor is around 1.5 . In a meta-analysis, mortality and morbidity, drug and alcohol misuse, risky sexual behavior, obesity, and criminal behavior were found as consequences of childhood maltreatment . According to Cutajar et al. , CSA increases the risk for several mental diseases like psychosis, affective, anxiety, substance abuse, and personality disorders. There is a particularly high probability for the development of post-traumatic stress disorders (PTSD) – exposure to CSA leads to an increased PTSD risk of 5.6 compared to non-CSA exposure. Accordingly, international studies show a high prevalence for PTSD after CSA, which ranges from 37% to 44% [10, 11]. However, victims of CSA do not only suffer from PTSD; comorbidity secondary to PTSD often develops during adolescence and early adulthood, moderated by the patient’s efforts to fight painful trauma-related emotions, for instance by using harmful substances and by developing suicidal, self-injurious, or other severely dysfunctional behavior [12, 13]. Early pregnancies and re-victimization occur at higher odds than in the general population [14, 15].
Given these negative consequences, it is obvious that abuse-related PTSD should be treated at an early stage. For children, there already exist evaluated interventions: a meta-analysis of 39 studies analyzing treatment results for children and adolescents with psychiatric symptoms after CSA reported a general effect size of g = 0.77 for PTSD symptoms in the 5 studies with controlled designs and an untreated comparison control group. For the other studies, the authors report pre-post effect sizes of g = 1.13 for PTSD . In contrast, few randomized controlled trials (RCTs) for PTSD therapy of adolescents were included in this meta-analysis – only two studies enrolling adolescents over 14 years of age used control conditions (waiting list/supportive treatment) and randomization [17, 18]. However, as the mean age in both studies was around 11 years, the majority of participants were children. To our knowledge, there exist only five studies examining treatment effects on post-traumatic stress symptoms after CPA or CSA among adolescent patients exclusively [19–23]. Being the first of their kind, these studies are undoubtedly important. However, most of them have methodological deficits like caseness not defined by PTSD diagnoses or the use of insufficient diagnostic instruments. Only the study of Foa et al.  meets the standards for controlled studies, although it only focusses on girls. In summary, adolescents beyond the age of 14 are inadequately represented in PTSD research so far.
Thus, the major goal of the presented project herein is to provide information on treatment efficacy in this understudied group. A highly effective cognitive behavioral therapy manual for adults, Cognitive Processing Therapy (CPT ), was adapted for adolescent patients with CSA/CPA-related PTSD  – the Developmentally Adapted Cognitive Processing Therapy (D-CPT). Four major adjustments were integrated in the protocol. First of all, the treatment intensity was increased by administering the middle part of the protocol in high frequency (approximately 15 sessions during four weeks) to enhance the adolescents’ motivation; applying treatment in such intensity was reported to be superior to the usual scheme of one session per week . Second, a commitment phase was included in the protocol in order to further build treatment motivation and to enhance therapeutic alliance as well as to establish the formal framework that is needed to conduct therapy. As survivors of childhood abuse often experience difficulties in emotion regulation, behavior and emotion management techniques, as used within Dialectical Behavior Therapy for PTSD (DBT-PTSD [27, 28]), were also integrated in D-CPT. Finally, special consideration was given to developmental tasks affecting the patient’s entire life, such as career choice, vocational training, and romantic relationships. Adolescent patients are at high risk of school or secondary education drop out, of starting relationships with abusive partners, or of becoming re-victimized. Therefore, we decided to specifically address these issues at the end of treatment.
D-CPT has already been successfully piloted; nearly all of the 12 participating patients showed large reductions of post-traumatic stress symptoms and, moreover, comorbid symptoms improved significantly as well . In October 2012, our research group started its work on the RCT and the associated studies. This article introduces its study protocol.
The current trial
The overall aim of this RCT is to demonstrate the efficacy of a newly adapted psychotherapy intervention protocol in comparison to treatment as usual (TAU) in the understudied population of physically and sexually abused adolescents and young adults suffering from PTSD. Severity of PTSD symptoms before and after therapy serves as a primary outcome. Secondary goals are to evaluate changes in general psychopathology and comorbidity, such as depression, borderline personality features, and dissociation. Thirdly, the trial will allow for an estimation of the efficacy of TAU in Germany, on which currently no data is available.
Adjunct projects will provide new insights in questions beyond treatment efficacy; electroencephalographic (EEG) parameters are collected in an experiment which aims to find neuronal correlates of threat processing evoked by different categories of emotional words. Preliminary studies could show that anxiety disorders modify the way threatening information is processed . By adapting these studies to the current project, multiple research questions may be answered. Namely, it will be possible to investigate differences in information processing between healthy subjects (control group), traumatized but healthy subjects (trauma control group), and traumatized subjects with PTSD (experimental group). In addition to this, the influence of D-CPT on information processing can be assessed on a psychophysiological level.
On the basis of questionnaires and videotaped sessions, potential predictors of treatment success are analyzed. As there is little research about handling PTSD in adolescents, also important variables influencing therapy outcome, such as treatment adherence, therapist competence, and working alliance, are not well studied . Equally sparse is data about societal costs for the treatment of PTSD and/or mental comorbidities like depression or anxiety disorders (direct costs) as well as PTSD-related loss of productivity (indirect costs). No study has ever investigated the indirect costs resulting from PTSD in adolescents and, so far, no study has analyzed any cost data of PTSD or PTSD-treatment in Germany. Using different questionnaires, these issues are addressed in the D-CPT-project.
Concerning the genetic basis of PTSD and therapy outcome, there are only very few (though promising) clinical studies indicating epigenetic changes in PTSD in humans (for example ). In our study, the analysis of epigenetic profiles of PTSD patients by saliva samples during the course of therapy is realized via high-throughput epigenetic profiling.