On Oct. 14, 2016, recruitment for the Adolescent Brain Cognitive Development (ABCD) study, the largest long-term study of brain development and child health in the U.S. began. The landmark study by the National Institutes of Health followed the biological and behavioral development of more than 10,000 children beginning at ages 9-10 through adolescence into early adulthood.

Recruitment was done over a two-year period through partnerships with public and private schools near research sites across the country as well as through twin registries.