The Aberrant Behavior Checklist (ABC) is a widely used measure in autism spectrum disorder (ASD) treatment studies. We conducted confirmatory and exploratory factor analyses of the ABC in 1,893 children evaluated as part of the Autism Treatment Network. The root mean square error of approximation was .086 for the standard item assignment, and in…

The dependability of externalizing behavior composites and subscale scores from the Behavior Assessment System for Children, Second Edition, Teacher Rating Scale-Child (Reynolds & Kamphaus, 2004) and the Achenbach System of Empirically Based Assessment, Teacher's Report Form for Ages 6-18 (Achenbach & Rescorla, 2001) was investigated.…