This article seems like it belongs in this thread, about new research on inconsistency of response times from adhd children, rather than consistently slow responses.
I don't know why this didn't occur to me before, but I guess it would be too easy to throw a very bad score by having just a few very very slow responses despite generally being about average in response time. Still not great, but interesting.

Inconsistent Performance Speed Among Children with ADHD...


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