Validation of English Language Skills?

Hi!
Somebody already checked about the different options to validate the language?!

Arizona gave me the following options:

1.-International English Language Test Service Academic Examination (IELTS)
2.- Test of English in International Communication TOEIC and Test of Spoken English (TSE)
3.TOEFL

Has anyone researched one of these? What's your opinion on this please?

Thanks