School Selection and Role


The ABCD Study® has enrolled 11,880 students and their families from all over the country. It is critically important that the participants in this study reflect the U.S. population of boys and girls, including children of diverse races and ethnicities, education and income levels, and living environments. To accomplish this goal, we partnered with public, private, and charter elementary schools in the continental U.S..

We identified all of the schools within a reasonable travel distance from each research site and selected a subset of the schools for enrollment. As enrollment occurred over a two-year period, we staggered our contact to schools so not all schools were approached at the same time. The careful selection of schools ensures that all demographic groups are included in the study so that the results are relevant for everyone.


Principals and administrators of partner schools were provided with information packets about the study and were asked to send them to families of all the 8-, 9-, and 10-year old students (at our expense), either through school folders, postal mail, or email lists.

All further contact with students’ families will be done by the researchers outside of school hours, either by phone, in the families’ homes, or at the Study Site. No part of this study will disrupt classroom activities or add an administrative burden beyond distribution of the information packets. We would also welcome the opportunity to visit schools and give presentations to faculty, students, and/or parents about the study and on general brain development, as well as provide instructional resources and updates as the study progresses.