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Gilliam Asperger’s Disorder Scale

James E. Gilliam, Ph.D.

Technical Information

The normative sample for the GADS included 371 representative subjects with Asperger's Disorder form the United States, Canada, and Australia.

Validity of the GADS
The GADS demonstrates a strong validity by (a) confirming the subscales are strongly related to each other and the overall diagnosis of Asperger's Disorder; (b) the items of the test and the definitions of Asperger's Disorder are directly related; and (c) the GADS scores discriminate persons with Asperger's Disorder from persons that have been diagnosed with autism and other behavioral disorders. The GADS is the only test of it's kind that has this type of discriminative ability.
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About the Author

James E. Gilliam, Ph.D.
Dr. Gilliam received his Bachelors of Science degree from Eastern Michigan University, Masters degree from State University College at Buffalo, and his Ph.D. from the University of Michigan.

Dr. Gilliam has taught both at the University of Wisconsin-Whitewater and University of Texas at Austin. He has also, consulted with parents, universities, state agencies, and schools in several countries on issues related to children with disabilities.
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James E. Gilliam, Ph.D.

Age Range 3 to 22 years

Administration Time 5–10 minutes

Administration Type

  • Parent-completed
  • Clinician/Teacher-completed
Qualification Level B

Format Handscored