Impairment and deportment responses to different methylphenidate doses in children with ADHD: The MTA titration trial

Objective: Results of the NIMH Collaborative Multisite Multimodal Treatment Study of Children With Attention-Deficit/Hyperactivity Disorder (MTA) were analyzed to determine whether a double-blind, placebo-controlled methylphe nidate (MPH) titration trial identified the best MPH dose for each child wi th attention-deficit/hyperactivity disorder (ADHD). Method: Children with A DHD assigned to MTA medication treatment groups (n = 289) underwent a contr olled 28-day titration protocol that administered different MPH doses (plac ebo, low, middle, and high) on successive days. Results: A repeated-measure s analysis of Variance revealed main effects for MPH dose with greater effe cts on teacher ratings of impairment and deportment (F-3 = 100.6, n = 223, p =.0001; effect sizes 0.8-1.3) than on parent ratings of similar endpoints (F-3 = 55.81, n= 253, P =.00001,effect sizes 0.4-0.6). Dose did not intera ct with period, dose order, comorbid diagnosis, site, or treatment group. C onclusions: The MTA titration protocol validated the efficacy of weekend MP H dosing and established a total daily lose limit of 35 mg of MPH for child ren weighing less than 25 kg. It replicated previously reported MPH respons e rates (77%), distribution of best doses (10-50 mg/day) across subjects, e ffect sizes on impairment and deportment, as well as dose-related adverse e vents.