Kelly 1989.

Study characteristics
Methods	Double‐blind, cross‐over trial with 2 interventions: MPH placebo Followed by long‐term follow‐up of 12 children out of 21 who continued to receive MPH. Follow‐up for an average of 16 months Phases Baseline Cross‐over trial Follow‐up
Participants	Cross‐over trial Number of participants screened: not stated Number of participants included: 21 (18 boys, 3 girls). 26 were initially included, but 5 children dropped out, 3 were removed by parents and 2 were disqualified because of a death in the family in 1 and a protocol procedural error in the other Number of participants followed up: 21, plus 2 participants who had been withdrawn but returned later for follow‐up Number of withdrawals to follow‐up: 0, but data for a few variables were not obtained for all participants Diagnosis of ADHD: DSM‐III Age: mean 9.3 years (range 8‐12) IQ: mean 100.7 MPH‐naive: 100% Ethnicity: white (62%), Hispanic/oriental [Asian]/black (14%), mixed race (24%) Country: USA Setting: outpatient clinic Comorbidity: oppositional disorder (14%), enuresis (38%) Comedication: not stated Other sociodemographics: 2‐parent household (95%)   Inclusion criteria ADHD diagnosis according to DSM‐III IQ > 80 Free of major health problems, neurological disorders or psychosis Exclusion criteria None stated
Interventions	Participants were randomly assigned to MPH or placebo MPH dosage: between 0.3 and 0.6 mg/kg/d in the short‐term phase Administration schedule: 2 time points/d Duration of each medication condition: not stated Washout before trial initiation: from noon to the following morning (i.e. the next day) Titration period: no
Outcomes	ADHD symptoms ACTerRS: ADD/H: rated before diagnosis, at cross‐over, at the conclusion of the short‐term protocol and again during long‐term follow‐up Conners' Parent Questionnaire: rated before diagnosis, at cross‐over, at the conclusion of the short‐term protocol and again during long‐term follow‐up
Notes	Sample calculation: not stated Ethics approval: yes Key conclusion of trial authors Findings indicate that many pre‐adolescents with ADHD exhibit low self‐esteem. Despite clinical response to medication, short‐term improvement in self‐esteem may not occur; however, long‐term, multi‐modal management that includes medication does appear to improve self‐esteem Comment from review authors The data that we used in the review were derived from the cross‐over period described 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: CIBA Geigy Pharmaceuticals provided placebos Email correspondence with trial authors: January 2014. Trial authors not able to provide us with further information
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	High risk	Child assigned in a double‐blind, cross‐over format to MPH followed by placebo or placebo followed by MPH
Allocation concealment (selection bias)	Unclear risk	Not stated
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Double‐blind
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Double‐blind
Incomplete outcome data (attrition bias) All outcomes	Low risk	Because data for a few variables were not obtained for all participants, a procedure for unbalanced analysis of variance was required and was accomplished by using the general linear model (GLM) procedure in the Statistical Analysis System (SAS) Selection bias (e.g. titration after randomisation → exclusion): no
Selective reporting (reporting bias)	Unclear risk	Not protocol identified