I can't get through the article.

But I used to be pretty active in the online gifted community. I was somewhat acquainted with folks involved in testing, developing new IQ tests, published authors blah blah blah. I'm not going to cite any sources. This is my understanding and it's about twenty years out of date.

First, the first test that gets cited as starting the whole IQ testing trend was never intended to measure intelligence. It was intended to measure school readiness for children of indeterminate age.

France had a problem:

City kids typically had known ages and we're already exposed to practices like standing in line. It was easy to assimilate them into the school system.

But rural kids often had no birth certificate and their age was not known and they additionally lacked the experiences of the city kids. There were cultural differences and trying to decide when the country kids should start school was proving problematic.

So they hired a guy, I think his last name was Binet, to create a test to help them decide when children were ready to start school.

This had nothing at all to do with measuring intelligence. But thereafter he developed additional tests and this eventually becy the Stanford-Binet.

Most IQ tests have a ceiling of about 140. Trying to test IQ above that is quite challenging. If you ceiling the test, your IQ is probably something above that.

In practice, if you aren't properly assessed by about age 7, we don't have the tools to accurately determine your IQ if it is above a certain range.

IQ tests are culture specific. This means that they aren't really accurate for immigrants or people of the wrong socioeconomic class. This means foreigners, poor people and people of color routinely score poorly on them and IQ tests thus have a long and sordid history of being used to justify racist, classist bullshit as well as anti-immigrant sentiment.

Twenty years ago, they were running into a problem: The tests good for testing very high IQs were old. They this contained culturally out of date questions. They needed a new test and wee running into trouble developing such.

IQ tests are additionally merely tools that can be useful in the hands of a trained professional for assessing someone. The tests themselves do a poor job of standing on their own. So online IQ tests are about as meaningful as those online quizzes that crap like "What kind of dog are you?"

Twice Exceptional kids -- gifted and disabled in some way -- probably benefit the most from getting properly assessed because they frequently have "average" performance while being horribly frustrated. Figuring out that a kid is actually bright and intellectually starving because no one realized he was bright can be life changing.

The best use of IQ tests is to try to understand your own needs. All testing is gamable and thus of questionable value for other purposes.

Getting some assessment helped me homeschool my sons appropriately. Beyond that, it's mostly useless bullshit in my opinion. The rich kids of the "insiders" tend to score well and other people tend to score less well, so, in practice, you can't cleanly separate out wealth, culture, education, etc from some kind of theoretical raw intelligence figure.