Development of a Brief Screening Tool for Repetitive Behaviors and Restricted Interests

Poster Presentation
Thursday, May 2, 2019: 11:30 AM-1:30 PM
Room: 710 (Palais des congres de Montreal)
A. Sturm1, S. Huang1, Y. S. Suh1, M. Kuhfeld2 and C. Kasari3, (1)UCLA, Los Angeles, CA, (2)Northwest Evaluation Association, Portland, OR, (3)University of California, Los Angeles, Los Angeles, CA

Repetitive behaviors and restricted interests (RB/RIs) have proven a difficult construct to accurately and validly measure, in part due to the heterogeneity of RB/RI symptom presentation by demographic and clinical characteristics. Additional work is needed to understand phenomenology and further refine existing measures.


The present study aimed to (1) use an existing measure of RB/RIs (Repetitive Behavior Scale – Revised; RBS-R) to identify RB/RIs that are present among individuals with ASD regardless of cognitive level, gender, or age and (2) propose a brief screening instrument for RB/RIs.


Participants included cross-sectional data compiled from the National Database for Autism Research, Autism Genetic Resource Exchange, and Simons Simplex Collection (N=3203). To evaluate frequency of endorsement across demographic and clinical characteristics, the sample was divided into 6 age and cognitive subgroups (age<6 & NVIQ<70, age 6-12 & NVIQ<70, age>=12 & NVIQ<70, age<6 & NVIQ>=70, age 6-12 & NVIQ>=70, age>=12 & NVIQ>=70), and 3 language subgroups based on ADOS module administered (Module 1 – single words, Module 2 – two word phrases, Module 3/4 - fluent speech). RBS-R item responses were recoded as either symptom present or absent. Items were selected as possible screening items if 50% of 5 of the 6 NVIQ/age subgroups (N=14) and all 3 of the ADOS subgroups (N=5) endorsed the item.


The sample included N=3203 participants with a diagnosis of ASD. Participants were 84% male, 67% Caucasian, 8.97 years of age on average (SD = 3.85; range 2-33), and had an average NVIQ of 83.36 (SD = 27.26). A total of N=14 of the 43 RBS-R items were endorsed by at least 5 of the 6 NVIQ/age subgroups and N=5 items by all 3 of the ADOS subgroups. The final item set included items that were endorsed by both at least 5 of the 6 age/NVIQ subgroups and all 3 of the ADOS subgroups (N=5). These items included “sensory (e.g., covers eyes)”, “becomes upset if interrupted in what he/she is doing”, “likes the same movie/music played continually”, “resists changing activities/difficulty with transitions”, and “fascination/preoccupation with one subject or activity”. These 5 items represented 3 of the 6 RBS-R subscales (stereotyped behavior, sameness behavior, restricted behavior). If the selection criteria were modified to include items endorsed by 2 of the 3 ADOS subgroups, “eating/mealtime (e.g., eats/drinks items in a set order)”, and “communication/social interaction (e.g., repeats same topics during social conversation)” would also be included (subscale: ritualistic behavior).


The present study supports the variability in presentation of RB/RIs by age, cognitive level, and language level. Despite the substantial differences in symptom presentation, there are several RB/RIs – notably sensory sensitivity - that are endorsed across individuals with ASD of different ages, cognitive abilities, and language levels. The items have the potential to serve as a more uniform screening tool for assessment of RB/RIs. Future work should confirm the results in other large population-based samples and determine if items can discriminate between ASD and other neuropsychiatric disorders that are characterized by repetitive behaviors (e.g., OCD).