I tend to think your family language environment does not explain the entire difference in verbal performance, although it certainly should be taken into consideration. It appears from what you've shared that he has probably been in immersive English education for the past three to four years, and had strong receptive English (at least) a year ago. For most non-disabled young children, that is enough to bridge most of the second language gap (although research does find that many learners are still working on academic language 7-10 years after entering the second language environment).
Regarding the WISC-IV vs WISC-V VCI, the two tests differ very little in this cluster (except that one of the WISC-IV subtests is now supplementary). Some items have been updated, while others remain quite similar. I would disagree that lack of experience with the -V is likely to have a significant impact on the VCI, unless the examiner is a particularly rigid one to begin with, in which case you would have more global issues with the accuracy of the results. This is actually one of the two indices that had the fewest changes. Anecdotally, I found the transition to be very smooth.
Actually, using the -IV instead of the -V would have weighted the score more heavily for verbal tasks, working memory, and processing speed, which probably would have taken the FSIQ down even further.
ETA: if you are concerned about second language effects, then it would be entirely appropriate to ask for an NVI to be calculated, as it may be less likely to discriminate against CLD (culturally-linguistically diverse) students in gifted program selection.
Last edited by aeh; 07/06/16 03:23 PM.
