Complex PTSD as proposed for ICD ‐11: validation of a new disorder in children and adolescents and their response to Trauma‐Focused Cognitive Behavioral Therapy

Background To evaluate whether the symptoms of children and adolescents with clinically significant posttraumatic stress symptoms ( PTSS ) form classes consistent with the diagnostic criteria of complex PTSD ( CPTSD ) as proposed for the ICD ‐11, and to relate the emerging classes with treatment outcome of Trauma‐Focused Cognitive Behavioral Therapy ( TF ‐ CBT ). Methods Latent classes analysis ( LCA ) was used to explore the symptom profiles of the clinical baseline assessment of N  =   155 children and adolescents participating in a randomized controlled trial of TF ‐ CBT . The treatment outcomes of patients with posttraumatic stress disorder ( PTSD ) and of patients with CPTSD were compared by a t ‐test for depended samples and a repeated‐measures ANOVA . Results The LCA revealed two distinct classes: a PTSD class characterized by elevated core symptoms of PTSD ( n  =   62) and low symptoms of disturbances in self‐organization versus a complex PTSD class with elevated PTSD core symptoms and elevated symptoms of disturbances in self‐organization ( n  =   93). The Group × Time interaction regarding posttraumatic stress symptoms was not significant. Pre–post effect sizes regarding posttraumatic stress symptoms were large for both groups ( PTSD : d  = 2.81; CPTSD : d  = 1.37). For disturbances in self‐organization in the CPTSD class, we found medium to large effect sizes ( d  = 0.40–1.16) after treatment with TF ‐ CBT . Conclusions The results provide empirical evidence of the ICD ‐11 CPTSD and PTSD distinction in a clinical sample of children and adolescents. In terms of relative improvement from their respective baseline posttraumatic stress symptoms, patients with PTSD and CPTSD responded equally to TF ‐ CBT ; however, those with CPTSD ended treatment with clinically and statistically greater symptoms than those with PTSD .