This is a research question need to be investigated. However, some countries are well equipped and work to develop their system toward gifted education, other country still crawling into it. The rest have no interest at all.

I aggree with you. It must be investigated. So, some smart policitians say that we examined it, so we would not invested in gifted education. You see that importance of gifted education decreasing :)

I agree it should be more investigated and also carry out more intervencione early in school.