a longitudinal study of 1,528 gifted children in California. The participants—3 to 19 years old—had IQs above 135. The study suggested that individuals who are gifted as children tend to exhibit greater success throughout their lifetimes, as measured by conventional societal standards, than those who are not. It also suggested that 2% of the population is gifted and that gifted children have better health and happier lives than their counterparts. [initiated in 1921 by Lewis M. Terman]