Background: Identification of possible personal indicators of risk for challenging behaviour has generally been through association in cross-sectional prevalence studies, but few analyses have controlled for intercorrelation between potential risk factors. The aim was to investigate the extent to which gender, age, presence of the triad of…

We examined whether clinically distinct subgroups can be derived from a sample of toddlers (n = 186) who failed the Modified Checklist for Autism in Toddlers, received a comprehensive clinical evaluation, and were diagnosed with an autism spectrum disorder (ASD). Three subgroups emerged from cluster analysis distinguished by (a) social,…

The purpose of this study was to investigate symptoms of comorbid disorders in infants and toddlers with autism spectrum disorders (ASDs). Research is scant on symptoms of co-occurring mental health conditions in this very young population. Method: Three hundred and twenty four participants were included in this study. Participants were classified…

Background: The diagnostic validity of autism spectrum disorder (ASD) based on Diagnostic and Statistical Manual of Mental Disorders (DSM) has been challenged in Down syndrome (DS), because of the high prevalence of cognitive impairments in this population. Therefore, we attempted to validate DSM-based diagnoses via an unbiased categorisation of…