Predictors and moderators of treatment outcome for single incident paediatric PTSD: a multi-centre randomized clinical trial.

Background: With few RCTs having compared active treatments for paediatric PTSD, little is known about whether or which baseline (i.e. pre-randomization) variables predict or moderate outcomes in the evaluated treatments. Objective: To identify predictors and moderators of paediatric PTSD outcomes for Eye Movement Desensitization and Reprocessing Therapy (EMDR) and Cognitive Behavioural Writing Therapy (CBWT). Method: Data were obtained as part of a multi-centre, randomized controlled trial of up to six sessions (up to 45 minutes each) of either EMDR therapy, CBWT, or wait-list, involving 101 youth (aged 8-18 years) with a PTSD diagnosis (full/subthreshold) tied to a single event. The predictive and moderating effects of the child's baseline sociodemographic and clinical characteristics, and parent's psychopathology were evaluated using linear mixed models (LMM) from pre- to post-treatment and from pre- to 3- and 12-month follow-ups. Results: At post-treatment and 3-month follow-up, youth with an index trauma of sexual abuse, severe symptoms of PTSD, anxiety, depression, more comorbid disorders, negative posttraumatic beliefs, and with a parent with more severe psychopathology fared worse in both treatments. For children with more severe self-reported PTSD symptoms at baseline, the (exploratory) moderator analysis showed that the EMDR group improved more than the CBWT group, with the opposite being true for children and parents with a less severe clinical profile. Conclusions: The most consistent finding from the predictor analyses was that parental symptomatology predicted poorer outcomes, suggesting that parents should be assessed, supported and referred for their own treatment where indicated. The effect of the significant moderator variables was time-limited, and given the large response rate (>90%) and brevity (<4 hours) of both treatments, the present findings suggest a focus on implementation and dissemination, rather than tailoring, of evidence-based trauma-focused treatments for paediatric PTSD tied to a single event.