One of the many frustrating aspects of working with kids who have Asperger's or are on the autism scale is assessment. In my experience, you may find out there is something your kid can do that nobody knew until they tested, but you are never going to get an accurate picture of what they can't do from a standardized or norm-referenced test.
The nature of Asperger's and autism usually means that you have to modify the administration of the test so that the statistical measures are not particularly valid anyway. "Standardized" does not apply to these kids, and without data that fits on a normal curve, you're never going to get an accurate IQ. WISC or any other results for students with Asperger's contain a little bit of information that may be valid, but they cannot be taken as a summary of cognitive ability the way you can use that data for other children.
