Valdizán Usón 2004.

Methods	A 12‐month cohort study
Participants	Number of participants screened: not stated Number of participants included: 170 Number of participants followed up: not stated Number of withdrawals: not stated Diagnosis of ADHD: DSM‐IV‐TR (subtype: not stated for the total sample. Subtype for the sample with polysomnography data: combined (40%), hyperactive‐impulsive (9%), inattentive (57%)) Age: mean 8 years old (range not stated) IQ: above 70 Sex: 121 males, 27 females Methylphenidate‐naïve: 100% Ethnicity: not stated Country: Spain Comorbidity: immunological diseases (33.3%) Comedication: no medication for sleep initiation Sociodemographics: not stated Inclusion criteria: First consultation between 1998 and 2002 ADHD according to DSM‐IV‐TR Free of other diseases Normal neurological examination without seizure, hearing loss or amblyopia Meet criteria for initiating methylphenidate treatment: ≥ 6 items of inattention, theta/alfa ratio > 1 in quantified EEG or predominance of theta in cerebral cartography, school or environmental repercussion Exclusion criteria: Gilles de la Tourette syndrome, autism spectrum disorders, dyslexia and dysphasia Epilepsy, especially absence seizures Mental retardation and obsessive‐compulsive disorder
Interventions	Methylphenidate type: immediate release Methylphenidate dosage: 10‐40 mg/day, adjusted as needed Administration schedule: morning and noon Duration of intervention: 12 months Treatment compliance: not stated
Outcomes	Non‐serious adverse events Reports of side effects Complete blood test Thyroid hormones and cortisol levels Nocturnal polysomnography (n = 46), initiated at 10 pm and disrupted at 7 am. Evaluated parameters: sleep efficiency, total registered time, latency time of sleep initiation, number of awakenings, total time of sleep and efficiency, duration of each phase and latency time of REM sleep
Notes	Sample calculation: not stated Ethics approval: not stated Funding/vested interest: not stated Authors' affiliations: not stated Key conclusions of the study authors: it is more likely that the ADD subgroup continues in the adult age and, although as a minority, immunological disorders and/or epileptiform paroxysms are associated. The effect of methylphenidate may be observed by seriated recording of digitalised cortical bioelectrical activity, with synchronic course to the clinical response Comments from the review authors: EEG was conducted every 6th month, but the methylphenidate treatment was paused 24 hours before, so we cannot use these data Exclusion of methylphenidate non‐responders/children who have previously experienced adverse events on methylphenidate: no Supplemental information regarding ethics approval, funding, protocol, patient demographics, and data not possible to receive through personal email correspondence with the authors. Emails sent several times in December 2013. No reply