The MTA began as a 14-month randomized trial of 579 children; its observational adulthood follow-up included 515 ADHD cases and 258 comparison participants. Consistent and inconsistent medication groups averaged 2.55 cm shorter than negligible-use participants, and consistent use averaged a further 2.35 cm shorter than inconsistent use.
Extended use of medication was associated with suppression of adult height but not with reduction of symptom severity in the naturalistic subgroups of the MTA.
The MTA began as a 14-month randomized trial of 579 children; its observational adulthood follow-up included 515 ADHD cases and 258 comparison participants. Consistent and inconsistent medication groups averaged 2.55 cm shorter than negligible-use participants, and consistent use averaged a further 2.35 cm shorter than inconsistent use. Medication-group height findings are observational associations in naturalistic subgroups, not randomized proof of causation or evidence that every stimulant-treated child loses height.