Akhondzadeh 2004.

Study characteristics
Methods	Parallel trial of haloperidol + cyproheptadine versus haloperidol + placebo
Participants	Inclusion criteria: children and adolescents aged 3 ‐11 years outpatients of children's clinic DSM‐4 clinical diagnosis of autism presenting with a chief complaint of severely disruptive symptoms related to ASD Exclusion criteria: previously received neuroleptics any psychotropic drug treatment 6 months prior to recruitment significant active medical problem Location/setting: speciality clinic for children at Roozbeh Psychiatric teaching hospital, Tehran, Iran Sample size: 40 Number of withdrawals/dropouts: none reported Gender: 24 boys, 16 girls Mean age: haloperidol + cyproheptadine = 6.4 years; haloperidol + placebo = 6.9 years IQ: not reported Baseline ABC‐I scores or other behaviours of concern: not reported Concomitant medications: not reported History of previous medications: not reported
Interventions	Intervention (haloperidol + cyproheptadine) for 8 weeks (20 participants): cyproheptadine was titrated up to 0.2 mg/kg/day; haloperidol was titrated up to 0.05 mg/kg/day Comparator (haloperidol + placebo) for 8 weeks (20 participants): haloperidol was titrated up to 0.05 mg/kg/day; placebo was not described
Outcomes	Primary outcomes: AEs Secondary outcomes: not reported Timing of outcome assessment: baseline, 2, 4, 6 and 8 weeks
Notes	Study start date: January 2002 Study end date: January 2003 Funding source: Tehran University of Medical Sciences Conflicts of interest: none declared
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Participants were randomised to receive cyproheptadine or placebo in a 1: 1 ratio using a computer‐generated code.
Allocation concealment (selection bias)	Low risk	The assignments were kept in sealed, opaque envelopes until the point of allocation.
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Quote: "Throughout the study, the person who administered the medications, the rater and the patients were blind to assignments."
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Quote: "Throughout the study, the person who administered the medications, the rater and the patients were blind to assignments."
Incomplete outcome data (attrition bias) All outcomes	Low risk	All 40 randomised patients completed the trial. No loss to follow up reported
Selective reporting (reporting bias)	Low risk	All primary outcomes appear to have been reported.
Other bias	High risk	Main author is also on the ethics committee at the university funding the study Main author is a peer‐reviewer for one of the journals in which some of their studies are published