This study began by comparing a group of children with high intelligence quotients with groups of children typical of the general population, to discover similarities and differences. Research was continued from the initial collection date of 1922 through the present, with follow-ups at approximately 5-year intervals, to explore long-term development of these children.

Through a process of teacher nomination and intelligence testing, 1,470 children in California with an IQ of 135 or above, were selected. In 1927-28, 58 siblings of the participants were added as a comparison group. Of the 1,528 participants in the study, 856 were male and 672 were female. The average date of birth for the sample was 1910.

In 1922, parents filled out an extensive questionnaire describing the child's birth and previous health, educational and social experiences, interests, and conduct. The children's teachers filled out a similar questionnaire. The children took a battery of intelligence, achievement, and personality tests and answered questionnaires about their interests in and knowledge of many matters. Several of these procedures were repeated in 1928. In 1936, the primary source of data was questionnaires filled out by the participants and their spouses. The 1940 follow-up covered development of personality and temperament, and included an elaborate study of marital relationships. In 1950, a similar follow-up added a lengthy biographical data questionnaire. The 1945, 1955, and 1960 follow-ups were more modest, with the 1945 follow-up focusing on the effects of the WWII military effort on the participants. In 1972, 1977, and 1982, the follow-ups were oriented to problems of aging, such as life satisfactions, retirement, living arrangements, and health and vitality. The data collected in 1986 included questions about changes in well-being, time use, importance of religion, perspectives on life accomplishments, changes in family relationships, concerns and goals.

The Murray Archive holds additional analogues materials for this study (microfiche copies of original record paper questionnaires from waves one through 12). If you would like to access this material, please apply to use the data.

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