I like the CTONI with some reservations.
It seems to be very tough for some of the kids with cerebral palsy with whom
I have used it. There was some research years ago by Martin Berko that indicated
that students with cerebral palsy did better on the Stanford-Binet L-M than on
the original Columbia Mental Maturity Scale. Marty hypothesized, as I recall,
that the Columbia's demands for categorizing and sequencing made the test more
difficult for the brain-injured kids with cerebral palsy. I wonder if the same
thing is operative with the CTONI.
A lot of the pictures seem to be outside the experience of many of the
children I see who have mobility disabilities. The graphics are a little
difficult in some cases.
The ceiling rule is, I find, awfully abrupt. A lot of the kids I see are
erratic in their responses and are able to pass a lot of items (with clearly
thoughtful decisions, not random guesses) beyond the first set of three errors
in five items. I can report that the student would have done "better,"
"a heck of a lot better," or "wicked better" if we could
have counted items beyond the ceiling, but I wish it had been normed with a
looser ceiling rule.
I like the fact that you have separate subtests, not just a global scale. You
can report a pictorial score vs. a geometric score, which is handy. With some
arithmetic, you can even figure out prorated scores for analogies, categories,
and sequences. I am mildly suspicious of the norms, which treat a score for 3
subtests, whether pictorial or geometric, identically. I would have guessed that
the norming sample would not have had identical performances on the two
different sets of items.
Test-retest reliability is reported (on a sample of 63 third and eleventh
graders) to be in the .80s for most subtests, high .80s for the pictorial total,
and low .90s for the geometric total and test total. Reported correlations with
the TONI-3 are modest (.75 and .77), which may be a good thing. Reported
correlations for 43 elementary students with LD are .82 with the TONI-2, .74
with the PPVT-R, .76 with the WISC-III VIQ, .70 with PIQ, and .81 with the FSIQ.
Unfortunately, the CTONI does not give the means of the tests. With 32 deaf
students of ages eight to eighteen, the correlation with the WISC-III PIQ was
.90 with subtests ranging from .70 to .90. The highest correlations were with BD
and OA.
Also, the CTONI norms are at one-year intervals, so a child of age 6-0 and
one of age 6-11 are on the same page in the norms tables. The total norming
sample was 2,901 (2,129 ages 6 through 18) tested mostly in 1995. 91% of the
sample had no known disability.