The International Trauma Questionnaire Child and Adolescent Version (ITQ-CA) in Portuguese: validation for children at risk

<b>Background:</b> Children and adolescents exposed to adversities, such as those in residential care or those affected by domestic violence (DV) but not in care, experience elevated rates of trauma, placing them at risk for both posttraumatic stress disorder (PTSD) and complex PTSD (CPTSD).<b>Objective:</b> Our objective is to validate the Portuguese adaptation of the International Trauma Questionnaire - Child and Adolescent Version (ITQ-CA) to assess for ICD-11 PTSD and CPTSD in at-risk Portuguese-speaking youths.<b>Methods:</b> The ITQ-CA was translated and culturally adapted following established guidelines. This study included 160 participants aged 7-17 years, comprising children in residential care and those exposed to DV. Confirmatory factor analyses (CFA) were conducted to test competing ICD-11 consistent latent structural models of PTSD and disturbances in self-organisation (DSO). Convergent validity was examined using the CRIES-13 and ITEM-CA, and divergent validity was assessed using the WHO-5. Exploratory factor analysis and network analysis were conducted as supplementary analyses and are reported in the Supplementary Materials.<b>Results</b>: CFA supported the two higher order correlated factors model with two-factor higher-order (PTSD and DSO), yielding adequate fit indices, <i>χ</i>²(52) = 104.189, RMSEA = 0.079, CFI = 0.923, TLI = 0.903. Internal consistency is strong (ω = 0.872; α = 0.871). The ITQ-CA demonstrated significant correlations with the CRIES-13 and ITEM-CA, supporting convergent validity, while negative correlations with the WHO-5 confirmed divergent validity.<b>Conclusion:</b> The Portuguese version of the ITQ-CA demonstrated strong psychometric properties, supporting its use as a valid and reliable tool for identifying PTSD and CPTSD symptoms in children and adolescents. Its integration into practice could support targeted trauma-informed interventions.