Personally, I think that IQ tests should not be used as the exclusive qualication for admission to GT programs. I agree that having a high IQ ought to be a valid standalone metric used to define giftedness but there should also be alternatives. An IQ test costs money and depending on familial income, potentially a relatively large chunk of money. Using IQ alone automatically excludes the majority of the kids from lower SES families. Said children are the most in need of publicly funded GT programs.
You make a good point. In NC, identifying giftedness is mandated and is part of public school policy. That said, unless there's a reason or a request for an individual test such as the WISC IV, a group test is given and we know how fallible a test like the CoGat is in identifying giftedness. Or at least it can seriously underestimate a gifted child's intelligence. It's quite expensive for the school to administer the individual tests, so I can understand why they don't use it for identifications, but the other methods seem to be blunt instruments at best..at least the way I understand them.
FWIW, our DS11 was identified as gifted in Kindergarten. An achievement test was administered and he needed to score in the top 99% in order to receive the 2nd highest level of services which is a pullout program in our district. The highest level is pullout plus independent learning guidance. He was tested in the beginning of first grade and scored in the 98% for verbal. He didn't qualify. His first grade teacher's assistant was the one who told the gifted teacher, test him in math--he's advanced in math. He scored a 99% and got into the program that way. (There were other criteria, but more subjective: teacher's recommendations, creativity display, etc)
5 years later he took the Explore Test and showed us that perhaps he wasn't mild to moderately gifted as we'd thought. We asked for an IQ, and the results confirmed what we learned on the EXPLORE test. Ironically, his VCI was significantly higher than his PRI. A flip-flop from the achievement test used to identify him, though his most recent achievement test corresponds with his IQ results, so most likely the change is due to asynchronous growth.
For some reason, I think the requirements have lowered to 95% in our county, but I'm not sure. I'll have to ask.
