I'm pretty sure that there aren't extended norms on the SB-V. But not totally sure. On the WISC-IV you definitely don't need to max out on FSIQ for them to apply, though. The idea seems to be to get a more accurate read when someone tops out on subtests, since the ceiling on those subtests may artificially limit the results.
On any test with decent headroom, if extended norms were only available for people with top-of-range FSIQ scores, they'd almost never be used, right? Also, they might be pretty much useless at that point, due to the subject exceeding the capability of the test to measure anything useful. I'm just thinking out loud here.
ETA: I found
this, but don't have time to read it right now. Looks like there might be the equivalent for the SB-V after all.
