Doctor of Philosophy (PhD)



Document Type



Interest surrounding the investigation of autism spectrum disorder (ASD) has increased exponentially since it was initially described over a half-century ago. With this passage of time our conceptualization of the ASD diagnosis has undergone multiple changes. An increasing trend in research has been an emphasis on early identification and intervention. This trend has brought about the creation and adaptation of multiple measures designed to inform early ASD diagnosis. Recently, the ASD diagnostic category underwent significant revisions. In response to revisions, it is necessary to adapt preexisting measures to reflect these significant changes in order to maintain diagnostic accuracy. The Baby and Infant Screen for Children with aUtIsm Traits (BISCUIT) is a triad of assessments specifically designed to assess infants and toddlers for ASD, comorbid conditions, and challenging behaviors. Initial investigations of each component of the BISCUIT have demonstrated that they are reliable and valid in the ASD population. However, the current scoring procedures include individuals diagnosed with both Pervasive Developmental Disorder, Not Otherwise Specified (PDD-NOS) and autistic disorder. The recent restructuring of the ASD category has effectively combined the various ASD diagnoses into a single diagnosis. The current studies identified new cutoff scores that reflect recent changes to the ASD diagnosis and maximized diagnostic sensitivity and specificity for each component of the BISCUIT and their individual subscales. Participants were initially separated into two diagnostic groups before being further separated into one of three age cohorts based upon age at time of initial evaluation. This approach allowed for direct comparisons between those with ASD and atypically developing peers while also considering the variable role of development on symptom manifestation. The cutoff scores identified by the current analyses maximized diagnostic sensitivity and specificity. Results of the current analyses are an initial step to demonstrating the utility of the BISCUIT for early identification following the revisions implemented by the Diagnostic and Statistical Manual of Mental Disorders-5 (DSM-5).



Document Availability at the Time of Submission

Release the entire work immediately for access worldwide.

Committee Chair

Matson, Johnny L.



Included in

Psychology Commons