With your brief description an evaluation is long overdue, as is a review of the validity of the original ADHD diagnosis since it was done in a time frame where ADHD was a very prevalent miss-diagnosis for individuals with Autism spectrum characteristics.
If you want to know if your child has EF differential issues vs. ADHD just review him to see if he can focus (off meds) for extended periods of time on area of his interest.
I just got back from a seminar by Tony Attwood (if you have not read his book “The complete guide to Aspergers C/2007 it is a must, and is available on
Amazon for $25), and he gave that example that he has about 100 characteristics which are part of the Aspergers evaluation, if a child has 80+ of these he(she) is Aspergers, if he has 60-80 he is PDD-nos (although he thinks calling it PDD-nos is ridiculously non descript). In the simplest terms PDD-nos is just an individual with Aseprgers characteristics who does not have enough to meet the clinical definition of but is still significantly impacted by the neurovariation. Just as a side it is his experience is that everyone has at least 10.
What will be involved in the evaluation is very dependent on whether it is being done by a clinician who is competent to do it (from my experience only about 10% of those doing it are). Try to find a clinician who “specializes” in Aspergers (at least 25% of practice involves this) and who has does continuing training in ASD for at least 200 hours per year by nationally recognizes works and clinicians. Usually these are found at major children’s medical centers.
Here is a link to a NIH page, which provides some info on what is involved, but there is a new draft proposal, which is much better and more comprehensive (but I can not find my link to it).
http://www.nimh.nih.gov/health/publications/autism/diagnosis.shtml
Basically the clinicians will have you and his teachers fill out questionnaires, give “tests” to you child to discover areas of weakness and strengths, an auditory processing evaluation is also done (although it sound like your child has already done one). A good clinician will spend 2-3 hours “playing” and talking with your child. Also they may try to eliminate other potential causes for any of the difficulties. There will also be an OT evaluation and a speech evaluation and some level of sensory variation audit.
With your description is sort of a “no brainer” that he is on the Autism spectrum it is just a matter of where and what services are needed to help him adapt to the neurotypical world to the extent that he wishes to.
It sounds like your child has “self adapted” pretty well so with the proper supports he should be able to make major additional progress. Just remember that while the “neurotypical world” creates challenges for individuals with Aserperges, the benefits of a “spectrum” mind are enormous so remember that he likely has abilities well beyond most neurotypicals.
bookwormde