I can tell you my experience with the RIAS my son took it at 5 to support a grade acceleration in K. He hit the ceilings on everything and the estimated his composite score to be 160+ because they couldn't scale in higher. In order to determine if he was DYS eligible they then administers the Standford Binet 5 months later. He received a IQ score of 132. With math added in and other factors it was a much more level score. I was surprised a little at the variation but the psychologist said it isn't too surprising because the RIAS is such a brief snap shot. So we did not find it highly correlated. It is possible his Standford Binet is a little low for his abilities and the RIAS too high. I always read threads like this because I find the variation interesting.
