Copyright @ 2009 American Academy of Child and Adolescent Psychiatry. Unauthorized reproduction of this article is prohibited. Medication Adherence in the MTA: Saliva Methylphenidate Samples Versus Parent Report and Mediating Effect of Concomitant Behavioral Treatment ELIZABETH PAPPADOPULOS, PH.D., PETER S. JENSEN, M.D., ALANNA R. CHAIT, B.A., L. EUGENE ARNOLD, M.D., JAMES M. SWANSON, M.D., LAURENCE L. GREENHILL, M.D., LILY HECHTMAN, M.D., SHIRLEY CHUANG, M.S., KAREN C. WELLS, M.D., WILLIAM PELHAM, PH.D., THOMAS COOPER, M.S., GLENN ELLIOTT, M.D., PH.D., AND JEFFRY H. NEWCORN, M.D. ABSTRACT Objective: Although research supports the use of appropriately administered stimulant medication to treat children with ADHD, poor adherence and early termination undermine the efficacy of this treatment in real-world settings. Moreover, adherence measures often rely on parent report of medication use, and their validity and reliability are unknown. Method: Drawing on data from 254 participants in the NIMH Collaborative Multisite Multimodal Treatment Study of Children With Attention-Deficit/Hyperactivity Disorder, we examine the discrepancy between parents’ verbal reports of medication adherence and physiological adherence measures determined via methylphenidate saliva assays collected at four time points during the 14-month treatment period. In addition, we examine the impact of physiologically documented medication adherence on parent- and teacher-reported outcomes through 14 months. Results: Overall, nearly one fourth (24.5%) of the saliva samples indicated nonadherence. Among subjects, 63 (24.8%) of the 254 participants were nonadherent on 50% or more of their repeated saliva assays. Only 136 (53.5%) of the subjects were adherent at every time point at which saliva assays were taken, indicating that some degree of nonadherence characterized nearly half of all other NIMH Collaborative Multisite Multimodal Treatment Study of Children With Attention-Deficit/Hyperactivity DisorderYtreated children. Findings also indicated that nonadherence produced greater deleterious effects in children in the medication-only condition compared with those receiving both medication and behavioral treatment. Conclusions: Same-day saliva methylphenidate assays suggest that nearly half of the parents are inaccurate informants of their child’s ADHD medication adherence and that parents may overestimate actual (physiological) adherence. This finding suggests the need for interventions to improve accuracy of parental report. Clinicians need to focus on adherence enhancement strategies to improve outcomes of children being treated with medication, particularly when benefits are suboptimal. J. Am. Acad. Child Adolesc. Psychiatry, 2009;48(5):00Y00. Key Words: medication, pharmacotherapy, methylphenidate, saliva levels. Clinical trial registration informationVThe NIMH MTA Study. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00000388. Accepted December 18, 2008. See end of text for author affiliations. The work reported was supported by cooperative agreement grants and contracts from the National Institute of Mental Health to the following: University of California, Berkeley: U01 MH50461 and N01MH12009; Duke University: U01 MH50477 and N01MH12012; University of California, Irvine: U01 MH50440 and N01MH 12011; Research Foundation for Mental Hygiene (New York State Psychiatric Institute/Columbia University): U01 MH50467 and N01 MH12007; Long Island-Jewish Medical Center U01 MH50453; New York University: N01MH 12004; University of Pittsburgh: U01 MH50467 and N01 MH 12010; and McGill University N01MH12008. The Office of Special Education Programs of the U.S. Department of Education and the Office of Juvenile Justice and Delinquency Prevention of the Justice Department also participated in funding. The opinions and assertions contained in this article are the private views of the authors and are not to be construed as official or as reflecting the views of the National Institute of Mental Health, the National Institutes of Health, or the Department of Health and Human Services. This article is the subject of an editorial by Dr. Philip L. Hazell in this issue. Correspondence to Peter Jensen, M.D., The REACH Institute, 450 Seventh Avenue, Suite 1107, New York, NY 10123; e-mail: PeterJensen@ TheReachInstitute.org. 0890-8567/09/4805-0000Ó2009 by the American Academy of Child and Adolescent Psychiatry. DOI: 10.1097/CHI.0b013e31819c23ed WWW.JAACAP.COM 1 J. AM. ACAD. CHILD ADOLESC. PSYCHIATRY, 48:5, MAY 2009 Copyeditor: Lorelie Eugenio