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Date of Award


Degree Type

Dissertation (On-Campus Access Only)

Degree Name

Doctor of Psychology (PsyD)

Committee Chair

Susan T. Li


Research indicates that both autism spectrum disorder (ASD) and attention-deficit/ hyperactivity disorder are commonly associated with deficits in neurocognitive and executive functioning, social communication and interaction, language skills, and adaptive functioning; however, there is limited research investigating all of these factors in children with these comorbid conditions. This dissertation study aimed to investigate the influence of ADHD symptoms on social interaction and communication skills in children with ASD after taking into account other significant factors. The present study utilized a two-factor differentiation of social communication and interaction, using specific summary scores (based on research from Bishop and colleagues, 2016) from the Autism Diagnostic Observation Schedule – Second Edition (ADOS-2). Data were collected from 140 children (79.3% male, 82.9% Caucasian, mean age = 138.9 months) who were part of a larger study at a medical research university in the Pacific Northwest. Measures included the ADOS-2, the Attention-Deficit Hyperactivity Disorder Rating Scale – Fourth Edition, various subtests from the Wechsler Intelligence Scale for Children, Fourth Edition, and the Behavior Assessment System for Children – Second Edition. ADHD symptoms were found to be unrelated to summary scores (i.e., basic social communication, interaction quality, and restricted and repetitive behaviors); and, covariates accounted for significantly more variance in the outcome variables than ADHD symptoms. There was no evidence that the effects of ADHD symptoms on summary scores varied based on the two-factors of social communication and interaction skills. Finally, there was no evidence of additive effects of ADHD symptoms in children with ASD. In summary, it is likely that these diagnoses, alone and combined, need further research to fully understand their etiology, diagnosis, and specific treatment approaches.

Available for download on Saturday, December 21, 2019