This study, also known as the Terman Study of the Gifted or the Genetic Studies of Genius, aimed to replace myths about intellectually superior children with documented facts. It examined the development and characteristics of gifted children into adulthood over more than 70 years. From 1922, the study recruited 1,528 children living in California, United States of America, born between 1900 and 1925, with an average age of 12 years and a Stanford-Binet Intelligence test score of 135 or higher. Participants were assessed at recruitment and followed up at 5 to 10-year intervals until 1999. Informant questionnaires were filled out by parents, teachers, participants, and spouses.