Comparing rates of ICD-11 and DSM-5 Posttraumatic Stress Disorder in Austrian children and adolescents in foster care: prevalence, comorbidity and predictors.

Background: The diagnostic criteria for Posttraumatic Stress Disorder (PTSD) differ between the DSM-5 and the ICD-11, affecting prevalence and associated metrics of PTSD.

Objective: Investigating the effects of the diverging DSM-5 and ICD-11 PTSD conceptualizations on prevalence and comorbidity rates, as well as predictor impact in a sample of foster children and adolescents using manual-specific measures.

Method: The sample consisted of = 145 foster children and adolescents. PTSD rates were assessed and compared utilizing the International Trauma Questionnaire - Child and Adolescent Version (ICD-11) and the Child and Adolescent Trauma Screen (DSM-5). PTSD comorbidities with Generalized Anxiety Disorder (GAD) and Major Depressive Disorder (MDD) were assessed. The predictive value of age, gender and cumulative trauma for PTSD was determined.

Results: A non-significant trend for higher DSM-5 (21.4%) vs. ICD-11 (16.7%) PTSD prevalence was observed. Significantly elevated DSM-5 vs. ICD-11 diagnostic rates were recorded in the re-experience (diff. = 18.3%) and hyperarousal (diff. = 10.1%) clusters. DSM-5 PTSD showed a non-significant trend for higher comorbidities with GAD and MDD. Gender and cumulative trauma predicted PTSD significantly and approximately equally according to both taxonomies.

Conclusion: The study supports the assumption that utilizing manual-specific PTSD measures in children and adolescents leads to higher rates of DSM-5 PTSD compared to ICD-11 PTSD. The exact methodological reasons for diverging diagnostic rates need to be analysed.