 :::Pesky, you might be interested in the Introduction to this study  While several diagnostic scales for children and adolescents with ASD are available (Attwood 1998; Ehlers et al. 1999), only one peer-reviewed scale, The Autism-Spectrum Quotient (AQ) was designed specifically for adults (Baron-Cohen et al. 2001). Its authors emphasize that it is useful in identifying autistic traits and as a screening instrument but not as a diagnostic tool. As a diagnostic tool, The Ritvo Autism Asperger Diagnostic Scale-Revised (RAADS-R)  will be more reliable, though perhaps less easy to administer than an orientative screening tool like AQ. —  