The thing we found interesting on the IAS back when it was used for my dd (I think that it was the last version then), was that it didn't specify how out of level the test you were using should be, just asked for out of level test scores and, if I recall correctly, gave points for scores at the 75th percentile or above on the out of level test. We used a test that was four grades above level (the EXPLORE when she was a young 9 y/o 4th grader). She had three parts (science, reading, and english) where she was btwn the 75th - around the 90th percentile at that time, but I recall thinking that, were one inclined to be seeking the most points possible on the IAS, one would just request a one grade out a level test.
I'd tent to agree with Kai, though, that I would be highly disinclined to make placement decisions based on a child's scores on a grade level test alone or an above level test unless the child would still be in the top bunch of the grade into which s/he was accelerated (not necessarily the top student, but one who could be an A student in accelerated classes).
Of course, I don't know that the OP is seeking acceleration, just info on what her dd's ITBS scores mean in terms of whether she should pursue options beyond the standard classroom.
