I was just looking over that report. This is striking:
These norms are used to further
differentiate highly gifted children (FSIQ or
GAI above 150) from gifted children (FSIQ
or GAI 130�150). The extended norms are
useful when a child�s score is the
maximum (ceiling) on two or more
subtests (e.g., obtains scaled scores of 18
or 19 points). These norms extend the
WISC�IV upper scaled score range to 28
points for subtests and 210 points for
composites. It is important to note that the
extended norms are not useful for most
children. Among the 2,200 cases in the
WISC�IV standardization sample, only
one child obtained a GAI score of 151 and
none obtained an FSIQ score of 150 or
higher. According to the bell curve, out of
20,000,000 same-age peers, only one
child would be expected to obtain a FSIQ
of 180 or higher.
That Bell curve is out of whack, if you ask me.
