The WASI has a very close relationship to the WISC (in fact, if a WISC is completed very soon after the WASI-II, they will use the subtests from the WASI in the WISC composites, instead of retesting those subtests), but not exactly the same structure. It also depends a bit on whether she had the 2- or 4-subtest version. (Did you get any other composites, or just the FSIQ?) There are also, critically, no WMI or PSI index scores, which are typically the ones most affected by ADHD. In short, the WASI-II FSIQ is reasonably predictive of the GAI, but not necessarily of the WISC-V FSIQ in learners whose WMI/PSI (aka, CPI) are notably different from the GAI, which describes quite a lot of persons with ADHD or certain LDs.
