In NYC they use the OLSAT, or did, for gifted programs because it is easy and cheap to administer and fair for those who cannot pay for IQ tests. I was astounded that it showed less gifted in the group in the Canadian study since so many kids score above 97th percentile in NYC.
I disagree with Ruf's view. They have shown that IQ points increase with string instrument study. They got 6-7 IQ points from one to two years of string instrument study and it was sustained and increased math scores.
Now you can be born with advantage, like being a poorer athlete than Joe next door, but you take Parissi training, improve your technique and it stays with you. You become a better athlete than Joe next door. You can say you were not born with the natural DNA or maybe you just weren't using it properly. Does it make a difference if the scores improve and sustain?
