At his age there really aren't any reliable IQ tests.
And, if I may speak freely, if his behavior has risen the point that he's been referred to IE screening, I would start to try to consider the possibility something really is going on with your son. Gifted-ness can cause a child to "look" a lot different from his or her peers, but at his age, behavior far enough outside of the norm to warrant testing is unlikely to be due solely to intelligence. I'm curious, what symptoms has he been showing that have caused concern?
At this point, I would try to keep an open mind (hard, I know, trust me!) and if therapy is recommended, please remember that anyone can benefit from therapy! A good therapist is not going to damage your child in anyway, and if they help him become happier all the better!
