I understand that the GAI is only supposed to be used if the difference between VCI and PRI is LESS than 23 points. So how is FSIQ supposed to be determined if the difference is 23 points or greater? My DS6 scored VCI-114
PRI-137
WMI-110
PSI-112 His report states his FSIQ was 126 and GAI was listed as 130. Does this sound right?

Yes, it sounds about right.

Hi--I'm a school psychologist and I think I can help. The GAI has absolutely nothing to do with the difference in scores between the VCI and PRI.

The FSIQ is ALWAYS obtained through the combination of all 4 indexes: VCI, PRI, PSI, and WMI--no matter how big or small the discrepancies are between them.

When a child exhibits Working Memory and/or Processing Speed Index scores that are significantly different than the VCI and PRI Index scores, then the GAI can be reported.

The GAI is ALWAYS obtained through the combination of the VCI and PRI indexes alone, leaving out the WMI and PSI scores.

From the perspective of a practicing school psychologist, I would never simply use the highest score and leave it at that when estimating a student's cognitive potential. In the case of significant and unusual discrepancies between Index scores on the Wechsler scales, I would report all of the Index scores and the FSIQ with the caveat that the discrepancies render little utility to the composite score. The same applies when a GAI is calculated, if there is significant and unusual discrepancy between the VCI and PRI. I would then follow up with additional assessments to find out the underlying reason for the discrepancy.