Shekim 1986.

Methods	Single‐center, randomized, double‐blind, placebo‐controlled, cross‐over trial Country: United States Number of study sites: 1 Statistical methods: NR
Participants	Sample size: 22 children/adolescents with an ADHD diagnosis according to DSM‐III criteria Dropouts: NR Psychiatric comorbid disorders: 0 Age range: 6 years to 12 years Mean age (SD): 9.75 (2.08) years Sex: 22 (100%) males ADHD subtype: NR
Interventions	Two interventions (all 22 children/adolescents participated in both interventions): Dextroamphetamine (short acting), weight‐based at 0.3 mg/kg twice a day, and titrated upwards during trial period, (n = 22) Placebo (n = 22) Duration: 28 days (2 x 14‐day treatment periods)
Outcomes	Relevant outcomes: Academic performance, assessed with Wide Range Achievement Test ‐ math subset Other outcomes: Wide Range Achievement Test ‐ spelling and reading subsets Monoamine oxidase activity Attention and impulsivity, assessed with Conners' Contininuous Performance Test
Notes	ClinicalTrials.gov identifier: not available Authors' affiliation: university Study funding: public funds
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Method of sequence generation not described
Allocation concealment (selection bias)	Unclear risk	Method of allocation concealment not described
Incomplete outcome data (attrition bias) All outcomes	High risk	Reasons for exclusions from the analysis not provided. Methods of analysis not described. Number of individuals included in the analyses not reported
Selective reporting (reporting bias)	Unclear risk	Study protocol not available and the possibility of reporting bias could not be assessed
Other bias	Low risk	Study appears to be free of other biases
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Blinding of participants and personnel not described
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Blinding of outcome assessment not described