Date of Completion


Embargo Period



Rhiannon Smith, Ph.D; Marianne Barton, Ph.D

Field of Study



Master of Arts

Open Access

Open Access


The DSM-5 diagnostic criteria for autism spectrum disorders (ASD) include substantial revisions, including the combination of the subcategories (Autistic Disorder, Asperger’s Disorder, and PDD-NOS) into one dimensional category of ASD, combining the social and communication domains into one, and requiring two rather than one repetitive and restrictive behaviors (RRBs). Concerns have been raised about the DSM- 5’s sensitivity for very young children, especially since RRBs may not manifest in this age group. In order to address concerns about the sensitivity of the DSM-5 ASD criteria in toddlers, the current study examined if toddlers who received an ASD diagnosis under the DSM-IV-TR criteria would maintain their diagnosis with the DSM-5 criteria. Children (n = 232) between the ages of 16 and 39 months (M = 25.95, SD = 4.49) who were part of a multi-site study examining the sensitivity and specificity of the Modified Checklist for Autism in Toddlers and who received an ASD or Non-ASD diagnosis were included in the study. Results suggested that 29% of toddlers who previously met an ASD diagnosis no longer did so with the new criteria. Relaxing criterion B by requiring one instead of two RRBs increased sensitivity while maintaining specificity. Because of the significant implications of early detection and intervention of ASD on outcome, it is important that the DSM-5 criteria reflect the presentation of ASD in toddlers. Requiring two RRBs may negatively impact the early detection of ASD because these behaviors may not have emerged in toddlers.

Major Advisor

Deborah Fein, Ph.D