Doctor of Philosophy (PhD)



Document Type



Since its first description, the definition of autism has varied as a function of emphases on particular defining features, changes to the age of onset, and confusion with other disorders. However, a recurring theme has been the importance of social impairments with evidence that specific social symptoms, such as joint attention deficits, are predictive of autism within the first or second year of life. In addition to the core domains of impairment, autism is associated with various medical conditions, intellectual disability, comorbid psychopathology, and problem behavior. This is alarming considering that there may be a true increase in the disorder’s prevalence and that it is associated with poor long-term outcomes. Fortunately, effective treatments exist that may alter the course of the disorder if administered early in a child’s life. A method to facilitate early intervention is through the early screening of autism with instruments such as the Baby and Infant Screen for Children with aUtIsm Traits (BISCUIT). The BISCUIT is a comprehensive assessment battery designed to measure autism symptoms as well as associated comorbid psychopathology and problem behavior. The primary purpose of the current investigation was to further develop the BISCUIT by creating an abbreviated scoring algorithm to enhance the measure’s diagnostic utility. Participants included 2,168 children ages 17 to 37 months enrolled in an early intervention program who were classified as having atypical development (n=1526) or an autism spectrum disorder (n=642). Discriminant function analysis (DFA) and receiver operating characteristic (ROC) analysis were conducted, resulting in a 5 item scoring algorithm with comparable diagnostic accuracy to the existing scoring procedure. Implications and directions for further research are discussed.



Document Availability at the Time of Submission

Release the entire work immediately for access worldwide.

Committee Chair

Matson, Johnny



Included in

Psychology Commons