Electronic Thesis and Dissertation Repository

Thesis Format

Integrated Article


Master of Arts




Leschied, Alan D. W



Childhood is an acutely vulnerable period for trauma, as it can significantly influence normative childhood development. Specifically, trauma resulting from maltreatment (i.e., neglect, sexual abuse, physical abuse, and witnessing domestic violence) offers unique challenges, as it often includes violations of boundaries and trust by caretakers. The aim of the present study was to examine child and youth maltreatment, and its impact on internalizing (e.g., mood disturbances) and externalizing behaviours (e.g., behavioural deviance). The sample was comprised of 9,002 participants who were assessed between the years of 2012-2017 on the interRAI Child and Youth Mental Health instrument (ChYMH). The ChYMH is a standard of care intake assessment used in many mental health agencies across Ontario, Canada, for individuals between four to 18 years of age. Individual and systemic forms of resiliency were of interest in predicting outcomes of maltreatment, which were found to mediate the relationship between maltreatment trauma and internalizing and externalizing behaviours. Further, significant differences in internalizing and externalizing scores were detected across no maltreatment, one type of maltreatment trauma, and polytrauma, with some deviations across sex and age groups. Implications for trauma-informed intervention and policy are discussed.