School-age children, especially those with autism spectrum disorder (ASD), often exhibit externalizing behaviour associated with a range of long-term negative consequences. Impairments in social...Show moreSchool-age children, especially those with autism spectrum disorder (ASD), often exhibit externalizing behaviour associated with a range of long-term negative consequences. Impairments in social cognition, and weaker expressive language level, are associated with these behavioural problems in children with ASD. Therefore, this study investigated the relationship between social cognition, specifically Theory of Mind (ToM), expressive language and externalizing behaviour in children with ASD aged 9 to 18 years. Understanding these complex dynamics of externalizing behaviour can enhance scientific knowledge, theoretical models, prevention and interventions strategies. A cross-sectional research design was employed, involving 56 participants (19% girls, 81% boys) with a mean age of 12 years. Diagnosis was made using the structured parent interview Autism Diagnostic Interview Revised (ADI-R). Psychopathology, namely externalizing behaviour, was examined in participants using the Childhood Behaviour Checklist (CBCL). Social cognition was identified using the Social Cognitive Skills Test (SCST). The Clinical Evaluation of Language Fundamentals (CELF) was used to evaluate expressive language skills with the subtest 'Formulated sentences'. The study offers valuable insights that may contribute to improved quality of life, mainly for boys with ASD aged 9 to 18 years seeking clinical help. One specific finding that may contribute to this is that expressive language skills can be improved indirectly by creating effective signalling, prevention, and intervention methods for social cognition (ToM), which in turn can enhance communication and interaction with others. Expressive language skills and ToM showed no association with externalising behaviour in this study. However, it is possible that these elements are indirectly related to other aspects of social cognition or to the broader group of people with ASD or gender. More research, especially longitudinal studies, are needed to better understand the complex dynamics to reduce externalising behaviour and prevent its associated adverse effects.Show less