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Date of Award


Degree Type

Dissertation (On-Campus Access Only)

Degree Name

Doctor of Psychology (PsyD)

Committee Chair

B.J. Scott


Research indicates that children with ASD and children with ADHD have deficits in their language generativity and communication abilities. However, few research studies have been conducted with children who have diagnosed ASD and comorbid ADHD. The first aim of this study was to investigate whether children with ASD and comorbid (and subthreshold) ADHD have more difficulty on word generativity tasks and higher ratings of impairment on parent report measures of communication than children with ASD alone and ADHD alone. Two hundred and twenty-eight children and adolescents from a university research study (68.9% male, 31.1% female, mean age=11.49) completed NEPSY-II Word Generation tasks, and their parents completed the Children’s Communications Checklist, 2nd Edition (CCC-2). Children diagnosed with ASD and comorbid ADHD were found to have significantly higher ratings of communication impairment than the ADHD only group (p<.001). All diagnostic groups had significantly higher ratings of communication impairment when compared to the TD group. The ASD and comorbid ADHD group produced fewer correct responses than the TD group (p=.037). Using a regression analysis, this study also found that meeting criteria for the diagnosis of ASD (not having or having ASD) was found to account for more variance in communication ratings (40.58%) than performance on word generativity measure (7.78%) and ADHD symptoms (5.29%) in the current sample. The results of this study suggest that children with ASD and comorbid ADHD have greater functional communication impairment that may require additional support despite similar generativity abilities to children with ASD or ADHD and typically developing controls. This study demonstrates support for considering the comorbid presentation of these two disorders when creating and implementing therapeutic interventions.

Available for download on Sunday, October 20, 2019