Comparison of scores on the Checklist for Autism Spectrum Disorder, Childhood Autism Rating Scale, and Gilliam Asperger's Disorder Scale for children with low functioning autism, high functioning autism, Asperger's disorder, ADHD, and typical development.
The CASD, CARS, and GADS all spot autism versus ADHD with near-perfect accuracy, but always screen for comorbid ADHD first.
01Research in Context
What this study did
The team gave three autism checklists to kids with different diagnoses.
They tested low- and high-functioning autism, ADHD, and typical kids.
Parents and clinicians scored each child on the CASD, CARS, and GADS.
What they found
All three tools sorted kids into the right group about 93-100% of the time.
Parents and clinicians agreed on 84-90% of the ratings.
The Checklist for Autism Spectrum Disorder (CASD) scored the highest accuracy.
How this fits with other research
Moss et al. (2009) ran a similar horse-race and found the 12-item CSI-4 PDD-only scale also separates ASD from ADHD.
Reus et al. (2013) adds a twist: kids who have both ASD and ADHD score higher on parent ASD scales, so you must check for ADHD first.
Ng et al. (2019) shows parent ratings and lab tests can disagree—use both kinds of data before you decide.
Why it matters
You now have three quick checklists that almost never miss the diagnosis.
Start with the CASD if you need to rule out ADHD fast.
Always screen for ADHD before you trust any ASD severity total, and pair rating scales with a brief direct observation.
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02At a glance
03Original abstract
Reliability and validity for three autism instruments were compared for 190 children with low functioning autism (LFA), 190 children with high functioning autism or Asperger's disorder (HFA), 76 children with attention deficit hyperactivity disorder (ADHD), and 64 typical children. The instruments were the Checklist for Autism Spectrum Disorder (designed for children with LFA and HFA), Childhood Autism Rating Scale (CARS) for children with LFA, and Gilliam Asperger's Disorder Scale (GADS). For children with LFA or ADHD, classification accuracy was 100% for the Checklist and 98% for the CARS clinician scores. For children with HFA or ADHD, classification accuracy was 99% for the Checklist and 93% for the GADS clinician scores. Clinician-parent diagnostic agreement was high (90% Checklist, 90% CARS, and 84% GADS).
Journal of autism and developmental disorders, 2009 · doi:10.1007/s10803-009-0812-6