The Repetitive Behavior Scale-Revised: independent validation in individuals with autism spectrum disorders.

A key feature of autism is restricted repetitive behavior (RRB). Despite the significance of RRBs, little is known about their phenomenology, assessment, and treatment. The Repetitive Behavior Scale-Revised (RBS-R) is a recently-developed questionnaire that captures the breadth of RRB in autism. To validate the RBS-R in an independent sample, we conducted a survey within the South Carolina Autism Society. A total of 320 caregivers (32%) responded. Factor analysis produced a five-factor solution that was clinically meaningful and statistically sound. The factors were labeled "Ritualistic/Sameness Behavior," "Stereotypic Behavior," "Self-injurious Behavior," "Compulsive Behavior," and "Restricted Interests." Measures of internal consistency were high for this solution, and interrater reliability data suggested that the RBS-R performs well in outpatient settings.