My DD took the WIAT-II, and that was one of the things that I was very disappointed about. In several subtests (Reading Comp and Writing were definitely among them) the test has pre-set start and end points. That meant that the reading comprehension passages did not include any that were more than a couple of years ahead of DD's age level. The same situation applied to the writing, which was very limited.
My understanding prior to this was that all individual achievement tests were designed to test up to the top level of the test (i.e. the tester keeps giving increasingly difficult questions until the stop criteria is reached). I believe that the WJ-III does do this for all subtests, but perhaps someone with more testing expertise can chime in on this. I'm curious myself, as we plan to test our DS at some point and I would prefer not to use the WIAT-II next time.
