I have 2 kids both with wide differences between VCI and PSI (and also PRI and PSI - they both did the WISC-IV) neither has been diagnosed with ADHD. DS9 has a 4 SD gap and we started this adventure into gifted because the school was convinced he had ADHD-Inattentive. He's now been through 2 full rounds of testing and both times he didn't come out with an ADHD diagnosis (he does have an LD in written expression though). He also did not test well on the Cogat. This year he moved to a gifted class and school has been going really well for the first time. He can focus really well when he is interested/challenged and properly accommodated for writing tasks, otherwise not so much. We've also spent a lot of time talking about how to deal with the frustration he feels with dealing with the LD challenge.
DD7 has a 2 SD gap and no one has ever suggested ADHD for her. We mostly tested because of her brother's scores and TBH I'm still kind of surprised at how similar the results were because in real life they are very different kids. She's breezed through school so far although this year we're starting to see cracks in her tolerance of "boring" worksheets.
