Examining Sensitivity to Developmental Changes on the Behavioral Inflexibility Scale

Purpose The study objective was to determine if the validated Behavioral Inflexibility Scale (BIS) is sensitive to the detection of developmental changes in inflexibility in a sample of autistic children. Methods Parents of autistic children (n = 146, 3–17 years) completed the BIS at two time points, one year apart, to examine change. Results The findings indicate the BIS is sensitive to the detection of developmental changes and that child-level variables are not associated with those changes. Children’s Time 1 BIS scores predicted children’s severity on an independent outcome measure. Finally, a relationship between total services children were receiving and change in BIS scores over time was not found. Conclusion The findings suggest the BIS is a reasonable candidate for consideration as an outcome measure.