P0082 - Title: How to Recognize Important Repetitive Behaviors Indicative of Autism Spectrum Disorder in Young Children.

Background: Early identification of children with ASD is essential to access early intervention (EI) services. Research has shown that children with more severe ASD symptoms are more likely to be recognized early (Zablotsky et al., 2017) and children with milder presentations tend to be diagnosed later (Fountain et al., 2011). Recent studies suggest this may be in part due to their lack of more obvious Restricted and Repetitive Behaviors (RRBS) (Gibbs et al., 2012; Barton et al., 2013), one of the two symptom domains for ASD diagnosis in the DSM-5.
Pediatric practitioners play an essential role in the developmental monitoring of infants and toddlers. Therefore there is a need for increased knowledge of how RRBs manifest in young children. The DSM-5 specifies four areas of RRBs, with the “lower order” stereotypies being more well-known (spinning, hand flapping, toe-walking,) than the “higher order” (insistence on sameness (IS) and restricted interests (RI)). Since some higher order RRBs are less common in the youngest children, it is important to know what they are and how early they may occur.

Purpose: To identify the type and frequency of restricted and repetitive behaviors of young children with ASD, through application of a newly developed instrument to better characterize RRBs in this age group.

Methods: Participants: Seventy children and their caregivers receiving diagnostic assessments for suspected ASD. Age range 12-47 mos, child age M=29.4 mos (SD=7 mos); 83% males.
Instruments: ASD diagnosis--Best Estimate Diagnosis was based on clinical interview, clinical examination, and either ADOS-2 or the Childhood Autism Rating Scale (CARS). RRBs -- The Infant-Toddler Restricted and Repetitive Behavior Inventory (IRRBI), Research Version, a 129-item checklist; domains correspond to DSM-5 diagnostic criteria for ASD. Method of administration is combined clinician observation and parent report. The IRRBI was designed to have more items and those specific to young children in order to address the gap in identification.

Results: The most frequently observed and reported RRBs are presented in Table 1. The most common items are in the Motor Stereotypies and Stereotypies with Objects, with specifics presented in the table. A new subscale in the IRRBI that focuses on play behaviors, and early repetitive/perseverate play behavior was reported or observed in 49%. When obsession with numbers, letters, and shapes were considered Restricted Interests RI frequencies were 49%, 44%, and 20%, respectively. IS in the daily routine did occur in this sample at 17% endorsement. Table 2 shows some examples of IS, and the age at which children began to manifest this type of RRB.

Conclusions: These findings may help clinicians to become more familiar with the range of RRBs in young children and enhance early detection of ASD in children who may have milder presentations.