Guerreiro 1996.

Methods	A cohort study of methylphenidate treatment
Participants	Number of participants screened: not stated Number of participants included: 24 Number of participants followed up: 22 Number of withdrawals: 2 Diagnosis of ADHD: DSM‐III diagnosis of ADHD (subtype: combined (around 80%), inattentive (around 20%)) Age: mean 9.1 years (range: 6.5‐13) IQ: normal, learning appropriately in regular schools Sex: 20 males, 4 females Methylphenidate‐naïve: not stated Ethnicity: not stated Country: Brazil Comorbidity: not stated Comedication: not stated Sociodemographics: not stated Inclusion criteria DSM‐III diagnosis of ADHD Followed in a private clinic of 1 of the authors
Interventions	Initiation of immediate‐release methylphenidate treatment: 5 mg once daily. Titrated if needed to a total maximum of 10 mg daily Administration schedule: once or twice daily. Treatment pause during weekends and holidays Duration of intervention: mean 12.6 months, range: 1 month ‐ 3 years Treatment compliance: not stated
Outcomes	Non‐serious adverse events: The occurrence of adverse events were assessed by the family and teachers
Notes	Sample calculation: not stated Ethics approval: not stated Funding/vested interests: not stated Authors' affiliations: the study was conducted at the Discipline of Child Neurology, Department of Neurology, Faculty of Medical Sciences (FCM), State University of Campinas (UNICAMP) Key conclusions of the study authors: the satisfactory and partial responses of methylphenidate treatment of ADHD observed in this study (79.1%) are in accordance with the literature, revealing therapeutic success in approximately 75% of the cases. We observed nausea and headache in 1 child, and only headache in another. Nausea can be controlled by lowering the dose; on the contrary, headache can be severe enough to result in cessation of treatment. Growth retardation is one of the possible side effects, which is of greater concern. Fortunately we did not observe this undesirable effect in our patients. Comments from the study authors: we might not have observed growth retardation in our study due to the use of low doses of methylphenidate and the recommendation of drug holidays Exclusion of methylphenidate non‐responders/children who have previously experienced adverse events on methylphenidate: no Supplemental information regarding ADHD subtype, IQ, and type of MPH received through personal email correspondence with the authors in December 2013 (Guerreiro 2013 [pers comm])