I want to thank Diana Senechal for guest-blogging for meso ably while I was on vacation. 

New York City parents prep their four-year-olds for IQ tests that will decide who gets into a “gifted” school, reports New York Magazine. But IQ tests aren’t very reliable for young children, especially at the high end of the scale.

Chance figures more prominently into high scores—a good night’s sleep, comfort with the tester—and lucky guesses on tough questions are worth more points than answers to midrange questions. In 2006, David Lohman, a psychologist at the University of Iowa, co-authored a paper called “Gifted Today but Not Tomorrow?” in the Journal for the Education of the Gifted, demonstrating just how labile “giftedness” is. It notes that only 45 percent of the kids who scored 130 or above on the Stanford-Binet would do so on another, similar IQ test at the same point in time. Combine this with the instability of 4-year-old IQs, and it becomes pretty clear that judgments about giftedness should be an ongoing affair, rather than a fateful determination made at one arbitrary moment in time.

Lohman estimates that only 25 percent of 4-year-olds who scored 130 or above would do so again as 17-year-olds.