Just in case others are interested, from what I have heard from my DS5's psych, The criteria is basically if a child's full scale is over 150 and if they got 19 on at least 2 of the subtests then they will do the EXIQ. But they still don't always if they are right on the line and meet that minimum criteria. I would bet that if a child had a 150 and they got 2 19's then their Full scale IQ would be above 150....but how much above I have no idea. That is beyond my area of knowledge.