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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, PhD

Second Advisor

Darryn M. Sikora, PhD


Autism Spectrum Disorders (ASD) are behaviorally diagnosed disorders with a proportion (male to female ratio) of 4:1 in the general population. Researchers have purported that sex-linked genes may play a significant role in ASD, given the striking gender ratio. An extension of this postulation is the Extreme Male Brain theory (EMB), which describes ASD as a continuum of normative gender differences. The aim of the present study was to take the EMB theory a step further and investigate whether ASD affects males differently than females, particularly in terms of adaptive and behavioral functioning. It was theorized that gender differences observed in typically developing children become more pronounced in the ASD population, if consistent with the extreme male theory. This study utilized the Child Behavior Checklist/1.5-5 and the Vineland Adaptive Behavior Scales, Second Edition to explore gender differences in adaptive and behavioral functioning within a group of 308 non-ASD children and a group of 338 ASD children. Across all analyses, no significant gender differences were observed, independent of diagnosis. Findings were consistent with previous literature regarding group differences between children with ASD and those without. This study was the first to investigate gender differences in terms of adaptive and behavioral functioning between non-autistic and autistic groups.


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