Post-Traumatic Stress Disorder Outcome Research: Why Moderators Should not be Neglected

Several psychotherapeutic treatments have been developed over the years for treating the symptoms of post-traumatic stress disorder (PTSD). But it remains still unclear which components of the complex treatment packages are necessary and most bene cial for PTSD symptom improvement. In PTSD outcome research, the randomized controlled trial (RCT) design has been applied in order to address this issue. However, meta-analyses repeatedly reported considerable variation between results from individual RCTs (i.e. between-study heterogeneity). A empts to explain such hetero- geneity led to the identi cation of relevant moderators of treatment e ects in PTSD RCTs. This study presents meta-analytic ndings, which show that factors, which are not part of the treatment (such as the investigators' preferences for a particular treatment or the complexity of the patients' clinical problems), impact on outcome in PTSD RCTs. We show that considering extra-therapeutic moderators in meta-analyses on PTSD RCTs may impact the conclusions and recommendations that may be deduced. The summarized ndings con rm the notion that no PTSD treatment consistently outper- forms the others and strengthen the position that even non-trauma-focused treatments may be bene cial PTSD treatments.