DuPaul 1996.

Study characteristics
Methods	4‐week, double‐blind, placebo‐controlled, cross‐over trial in which participants were randomly assigned to 3 doses of MPH: 0.16 mg/kg 0.29 mg/kg 0.42 mg/kg placebo
Participants	Number of participants screened: not stated Number of participants included: 24 (19 boys, 5 girls) Number of participants followed up: 24 Number of withdrawals: 0 Diagnosis of ADHD: DSM‐III‐R (subtype not stated) Age: mean 11.09 years (range 9‐15) IQ: > 70 MPH‐naive: not stated Ethnicity: white (100%) Country: USA Setting: outpatient clinic Comorbidity: ODD (21%), CD (% not reported) Comedication: not stated Other sociodemographics: children were primarily from lower‐middle class and middle class families Inclusion criteria Parent and/or teacher referral to an outpatient ADHD clinic due to reported problems with inattention, impulsivity and/or overactivity Parent interview indicating that child met DSM‐III‐R (American Psychiatric Association, APA 1987) criteria for ADHD Independent diagnosis of ADHD by psychologist and paediatrician using DSM‐III‐R criteria for ADHD Parent or teacher ratings on the Attention problem scale of the CBCL (Achenbach 1991), resulting in a T score ≥ 65 (i.e. 1.5 SD above the mean) ≥ 9 years old and able to read self‐report questionnaires independently Exclusion criteria Evidence of mental disability, gross sensory or motor disabilities, seizure disorder, autism, psychosis, tic disorders or Tourette’s syndrome, or significant cardiac problems Currently receiving psychotropic medication
Interventions	Participants were randomly assigned to 1 of 6 possible drug condition orders of low‐ (0.16 mg/kg; SD 0.08), moderate‐ (0.29 mg/kg; SD 0.11 kg) and high‐dose (0.42 mg/kg; SD 0.14) MPH and placebo Administration schedule: twice/d, morning, noon Duration of each medication condition: 1 week Washout before trial initiation: not stated Titration period: none Treatment compliance: no participant was removed from the investigation for non‐compliance (e.g. > 1 day of failure to administer medication as scheduled)
Outcomes	ADHD symptoms ADHD‐RS: teacher and parent ratings Non‐serious AEs Barkley Side Effects Rating Scale (17 items, 0 = absent, severity rated from 0‐9): rated by participants at the end of each dosage condition
Notes	Sample calculation: no information Ethics approval: Human Subjects Research Board at the University of Massachusetts Medical Center Comments from trial authors Conclusions based on present findings are limited by several factors Among others, sample size may have diminished power to detect MPH effects on key variables, especially analyses of side‐effect ratings Also results are generalisable only to children with ADHD between 9 and 15 years of age Exclusion of MPH non‐responders/children who have previously experienced AEs while taking MPH before randomisation: no Any withdrawals due to AEs: no Funding source: not stated Email correspondence with trial authors: January 2013‐August 2013. Emailed first trial author regarding additional information. Not able to get all data requested, as trial author no longer has these data
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Children were randomly assigned to 1 of 6 possible orders of MPH dosage
Allocation concealment (selection bias)	Low risk	Medication was prepared by the hospital pharmacy in increments of 5 mg and packaged within opaque gelatin capsules
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Participants, their parents and teachers and the research assistant in charge of collecting data were blinded to the order of medication
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Participants, their parents and teachers and the research assistant in charge of collecting data were blinded to the order of medication
Incomplete outcome data (attrition bias) All outcomes	Low risk	No Selection bias (e.g. titration after randomisation → exclusion): no
Selective reporting (reporting bias)	Low risk	No indication of reporting bias. Analyses on all dependent measures in the trial are reported in the article