Maybe, to some degree, that's true. But... I never spent any time learning how to take IQ tests, and have been tested at multiple stages - specifically IQ tests, and also the ACT/SAT.
First tests I remember, I was 9. Then ACT at... 15? Maybe it was 16. Then more IQ tests (3 different ones, IIRC) about 4 years ago. All showed me to be in the same X percentile, with a very small degree of variance between tests and over 30+ years of taking them.
And to repeat, I never spent any time learning how to 'take' a test. It was actually disappointing to get the test results and compare them to ~30 years earlier, and not see any change. I thought I'd have been 'smarter' as an adult, but I do realize it's not really testing that so much as... raw capacity perhaps? That hasn't demonstrably changed, despite all the life that's happened to me. No major health issues tho; I can certainly imagine that had I had a brain injury, my IQ test scores would be lower.
First tests I remember, I was 9. Then ACT at... 15? Maybe it was 16. Then more IQ tests (3 different ones, IIRC) about 4 years ago. All showed me to be in the same X percentile, with a very small degree of variance between tests and over 30+ years of taking them.
And to repeat, I never spent any time learning how to 'take' a test. It was actually disappointing to get the test results and compare them to ~30 years earlier, and not see any change. I thought I'd have been 'smarter' as an adult, but I do realize it's not really testing that so much as... raw capacity perhaps? That hasn't demonstrably changed, despite all the life that's happened to me. No major health issues tho; I can certainly imagine that had I had a brain injury, my IQ test scores would be lower.