Summary (participants)

Number of participants screened Number of participants included Number of participants randomly assigned to methylphenidate and control Number of participants followed up in each arm: methylphenidate and control Number of withdrawals in each arm: Methylphenidate and control Diagnostic and Statistical Manual of Mental Disorders, Third Edition (DSM‐III) diagnosis of attention deficit hyperactivity disorder (ADHD) (combined (%), hyperactive‐impulsive (%), inattentive (%)) Age (years) (mean, range) IQ (mean, range) Sex (male, female) Methylphenidate naive (%/number) Ethnicity (white (%), African American (%), Asian (%), Hispanic (%), other (%)) Country Comorbidity (type %) Comedication (no/yes) Sociodemographics (e.g. double or single parent family, low, middle or upper class) Inclusion criteria Exclusion criteria