What decides a high IQ?
Good memory, math skills, logical thinking? I really don’t know what the-powers-that-be value in order to make a high IQ.
Read “The Bell Curve”. It’s very interesting, readable, and goes into this issue. The short answer is that higher IQ correlates very strongly with superior performance on memory tests, math tests, logical thinking tests, etc. So most tests that purport to test intelligence (generally testing many of these factors) do a good job of coming up with an “IQ” that then turns out to be a good predictors of other things requiring intelligence.
I would think that political correctness would destroy the data base for the last couple of decades. Not just for race; but, the accommodation of Feminism and Socialism and the illogic of new age religions.
Researchers need to keep double books!