Dirksen 2002.

Methods	A multicentre, open‐label, cohort study of the effectiveness and tolerability of an extended release methylphenidate in treated and untreated children and adolescents with ADHD over 3 weeks
Participants	Number of participants screened: 332 Number of participants included: 310 Number of participants initiating treatment: 308 Number of participants followed up: 287 Number of withdrawals: 23 Diagnosis of ADHD: DSM‐IV (subtype: not stated) Age: mean 11.0, range 6‐17 years old IQ: > 80 Sex: 222 males (72.1%), 86 females (27.9%) Methylphenidate‐naïve: 41% Ethnicity: white (82.1%), African American (10.4%), others: (7.5%) Country: USA Comorbidity: none Comedication: not stated Sociodemographics: not stated Inclusion criteria Children and adolescents aged 6‐17 years A confirmed DSM‐IV diagnosis of ADHD Either untreated or currently receiving treatment with an approved methylphenidate product Vital signs and laboratory assessments within the normal range Blood pressure within the 90th percentile for height and gender Females pre‐menarchal, sexually abstinent, or using a medically acceptable form of birth control and having a negative pregnancy test Exclusion criteria Comorbid psychiatric disorder Concurrent illness IQ less than 80 Inability to understand or follow directions History of tic disorder, Tourette syndrome, seizures, glaucoma, hyperthyroidism or significant cardiovascular disease Non‐response to methylphenidate Use of excluded medications or medications that affect blood pressure or heart rate Personal or family history of substance abuse Pregnancy or a significant risk of pregnancy Participated in another drug study in the previous 30 days
Interventions	Methylphenidate type: extended release methylphenidate hydrochloride (Metadate CD) Methylphenidate dosage: 20‐60 mg Administration schedule: once daily, in the morning before breakfast Duration of intervention: 3 weeks Treatment compliance: not stated Dosage was titrated on a weekly basis according to clinical judgement
Outcomes	Safety and tolerability were assessed by laboratory tests, vital signs and adverse events collected through spontaneous reports by parents, general questioning of the child, and investigators' observations. Assessed at 3 study visits with 7 days apart Adverse event data were collected as pre‐study events (to assess the presence of pre‐existing symptoms and events)
Notes	Sample calculation: not stated Ethics approval: approved by the Institutional Review Boards at each study centre Funding: Celltech Americas Inc. Vested interest/authors' affiliations: 3 of the 4 authors were employed by Celltech Americas Inc. Key conclusions of the study authors: methylphenidate hydrochloride is effective and well‐tolerated for clinical use in ADHD Comments from the study authors: the absence of a placebo control group makes it difficult to determine whether there was bias in evaluating effectiveness or relatedness of adverse events Exclusion of methylphenidate non‐responders/children who have previously experienced adverse events on methylphenidate: yes Supplemental data requested through personal email correspondence with the study authors with in March 2014. No reply