If it were me, I would not get an IQ test right now. The chance for an inaccurate result at four, is high-- especially if your DS is having some issues with impulse control and frustration.

Case in point-- my DS took an entrance exam for school right at age five. He decided he was interested in the math section and scored in the 99th percentile. He decided he was not interested in the literacy section and scored in the 4th percentile.

We spent months wondering if had a learning disability, until he took another test putting him a couple of years above grade level in reading and language scores in the 99th percentile. I guess he decided that he was more interested in the test the second time. See what I mean?