Differences in Stereotypic Behavior in Adults Diagnosed with Autism Spectrum Disorders Using the DSM-IV-TR and the DSM-5

The purpose of the current study was to investigate differences in the frequency of stereotypic behavior (e.g., engaging in repetitive activities; repetitive body movements such as rocking, spinning, handflapping; repetition of words or sounds; and perseveration on specific topics) using a psychometrically sound measure, the Diagnostic Assessment for the Severely Handicapped, second edition (DASH-II). The sample investigated included 261 adults with severe or profound intellectual disability (ID), 51 of whom met criteria for ASD according to the DSM-5 ; 84 of whom met criteria for the DSM-IV-TR , but no longer qualify for an ASD diagnosis with the new criteria; and a control group of 126 adults who did not qualify for an ASD diagnosis according to either version of the DSM. The DSM-5 captured a more impaired population in terms of stereotypies, though a significant difference remains between those who no longer meet criteria and a control group with ID who did not meet criteria for ASD under either version of the DSM . Highlights • Approximately 38 % of adults with ID currently meeting criteria for autism under the DSM-IV-TR did not meet the DSM-5 criteria. • Those who continued to meet criteria for ASD had higher scores on the DASH-II stereotypy subscale. • People meeting DSM-IV but not DSM-5 criteria had significantly more stereotypic behavior than adults without ASD.