A Study of Assessments: A Comparison of Bsiq and RBS-R Reported Rrbs

Background:  Restricted and repetitive behaviors (RRBs) include a broad category of behaviors which are considered core characteristics required for a diagnosis of Autism Spectrum Disorder (ASD) according to the Diagnostic and Statistical Manual (DSM-V; American Psychiatric Association, 2013). Parents have often reported that RRBs can be the most stressful aspect of ASD (Bishop, Richler, Cain & Lord, 2007). RRBs can be subdivided into repetitive and sensory motor behaviors (RSM) and Insistence on Sameness behaviors (IS). This study analyzes the difference between RRB IS, RSM, and Total composite scores as measured by two assessments: the Behavior and Sensory Interest Questionnaire (BSIQ) (Hanson et. al. 2015) and the Repetitive Behaviors Scale – Revised (RBS-R) (Bodfish, Symons & Lewis, 2000).

Objectives:  This study aims to assess if the BSIQ and RBS-R report the same number of presenting RRBs. 

Methods: A sample of 513 children with ASD (82% male) was drawn from the Simons Simplex Collection and the Boston Autism Consortium. Participant ages were between 24-216 months, (mean=92.3, SD=45). ASD diagnosis was verified with the Autism Diagnostic Observation Schedule (ADOS) and Autism Diagnostic Interview-Revised (ADI-R). Parents were administered the BSIQ, designed to evaluate the number, type, and intensity of RRBs, by a trained clinician. The RBS-R, also designed to evaluate the number, type, and intensity of RRBs, is a parent report survey that parents completed independently. Preliminary analysis included descriptive statistics and a series of paired-T tests to determine if a significant difference exists between IS, RSM, and Total composite scores on the BSIQ and RBS-R within the same population. The severity scale on both measures (0-3) was collapsed to a Yes/No binary for all statistics. 

Results:  Preliminary analyses revealed a significant difference (.000) in the percent of behaviors reported on the BSIQ versus the RBS-R for RSM scores. 25% of respondents reported the presence of an RSM behavior on the BSIQ as compared to 29% on the RBS-R. Preliminary analyses revealed a marginally significant difference (.09) in the percent of behaviors reported on the BSIQ versus the RBS-R for IS scores. On average, 22% of respondents reported the presence of an IS behavior on the BSIQ as compared to 24% on the RBS-R. Preliminary analyses revealed that there is not a significant difference (.000) in the percent of overall behaviors reported on the BSIQ versus the RBS-R for Total Scores.

Conclusions:  These preliminary analyses suggest that respondents are more likely to report a behavior on the RBS-R than on the BSIQ. It is possible that the BSIQ’s specificity and clinical judgment results in less RRB quantity but a more accurate account of presenting RRBs and their severity. Further research should examine if a difference is reported specifically in the severity of behaviors on the RBS-R versus the BSIQ. As well, additional studies are required to determine which assessment method provides the most accurate measurement of presenting RRBs.