Validating the Repetitive Behavior Scale-revised in young children with autism spectrum disorder.

This study examined the factor structure of the Repetitive Behavior Scale-Revised (RBS-R) in a sample of 287 preschool-aged children with autism spectrum disorder (ASD). A confirmatory factor analysis was used to examine six competing structural models. Spearman's rank order correlations were calculated to examine the associations between factor scores and variables of interest. The 3- and 5-factor models were selected as preferable on the basis of fit statistics and parsimony. For both models, the strongest correlations were with problem behavior scores on the Child Behavior Checklist and repetitive behavior scores on the ADI-R. Developmental index standard scores were not correlated with factors in either model. The results confirm the utility of the RBS-R as a measure of repetitive behaviors in young children with ASD.