We are announcing a new study! The READY Study is an extension of the ACTIVE study and will examine EEG correlates of stimulant medication response. Previous ACTIVE study participants who have ever taken Methylphenidate are eligible for this study. The goal of this study is to examine potential biomarkers of methylphenidate response among children. The investigation involves a short online questionnaire about your child’s medication history and also includes a short parent phone interview. For more information, please contact Tara Rutter, M.S. firstname.lastname@example.org.