Psychometric properties of a DTD self-report scale among Portuguese adolescents from the community

Background: Developmental Trauma Disorder (DTD) has been proposed as a developmentally informed framework to describe the pervasive dysregulation associated with chronic interpersonal trauma in childhood. DTD has been assessed by a validated structured interview, but no study has validated a self-report measure of DTD symptoms or examined its factorial structure in community adolescent samples. In addition, measurement invariance across sex has not been investigated, despite evidence of sex differences in trauma exposure and trauma-related symptoms.Objective: To evaluate the psychometric properties of a self-report measure of DTD symptoms in a community sample of Portuguese adolescents by testing factorial structure, internal consistency, convergent and discriminant validity, and measurement invariance across sex.Methods: A school-based sample of 444 adolescents aged 11–16 years completed a self-report DTD symptom scale and other theoretically related measures. Confirmatory factor analyses compared alternative models of DTD symptom organisation. Measurement invariance across sex was tested using the best-fitting model. Convergent and discriminant validity were examined using Pearson correlations and group comparisons based on trauma exposure criteria.Results: A second-order model with three first-order factors provided the best fit. Configural and metric invariance across sex were supported, with partial scalar invariance after freeing two intercepts. Internal consistency was good to excellent, and evidence for convergent and discriminant validity was observed.Conclusions: The findings provide the first evidence that DTD symptoms can be assessed using a self-report measure with acceptable factorial validity, reliability, and cross-sex comparability in a community adolescent sample.