From experience with my 2e son...his first IQ test had full scale IQ as 91 and then 3 years later (after ABA, etc. therapies) was 148. So I say, yes 2e-ness does affect IQ! But the psychologist wrote on the first test the standard statement saying something like "this is a correct and true demonstration of IQ and will expect to vary by 3 points," or whatever they put at the end of the test. But I haven't heard of anyone else who has had such a dramatic difference. Who knows?! Nan smile