Malone 2001.

Study characteristics
Methods	Parallel trial of olanzapine versus haloperidol
Participants	Inclusion criteria: children aged 5‐17 years (mean age 7.8 +/‐ 2.1) primary diagnosis of PDD (DSM‐4 criteria) at least moderate impairment on ≥ 2 of the first 28 items of the Children's Psychiatric Rating Scale at baseline Exclusion criteria: "major medical problems such as cardiac, liver, endocrine, or renal diseases, or seizure disorders or gross neurological deficit, treatment with concomitant psychotropic medication, or a history of previous treatment with haloperidol or olanzapine". Location/setting: not reported Sample size: 12 Number of withdrawals/dropouts: none reported Gender: olanzapine 4/6 male both groups Mean age: 7.8 years IQ: 2/6 and 3/6 (olanzapine and haloperidol) had severe intellectual disability, 3 and 2 had moderate intellectual disability, 1 in haloperidol had mild intellectual disability, and 1 in olanzapine had normal cognitive functioning. Baseline ABC‐I or other BoC: not an outcome Concomitant medications: psychotropic drug use during trial was not permitted History of previous medications: 4 participants had no history of prior psychotropic drug use
Interventions	Intervention (olanzapine) for 6 weeks: the starting dosage of olanzapine was 2.5 mg every other day for participants who weighed ≤ 40 kg and 2.5 mg/day for participants who weighed > 40 kg. In general, dosages could be increased in 2.5‐mg increments up to 5 mg a week, as needed. The maximum dosage for olanzapine permitted by the study protocol was 20 mg/day. Comparator (haloperidol) for 6 weeks: the starting dosage of haloperidol was 0.25 mg/day for participants who weighed ≤ 40 kg and 0.5 mg for participants who weighed > 40 kg. In general, dosages could be increased as clinically indicated in 0.5‐mg increments up to 1 mg a week, as needed. The maximum dosage for haloperidol permitted by the study protocol was 5 mg/day. Mean daily dose 1.4 mg/day (+/‐0.7)
Outcomes	Primary outcomes: AEs Secondary outcomes: none reported Timing of outcome assessments: baseline and endpoint
Notes	Study start date: not reported Study end date: not reported Source of funding: supported, in part, by a grant from Lilly Research Laboratories (Investigator‐Initiated Study) Conflicts of interest: none disclosed
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "Randomisation was performed by use of a computer‐generated list"
Allocation concealment (selection bias)	Unclear risk	Details not provided
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Details not provided
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Details not provided
Incomplete outcome data (attrition bias) All outcomes	Low risk	13 were originally enrolled in the study and 1 withdrew consent before beginning study medication. 12 were included in the analysis.
Selective reporting (reporting bias)	Low risk	The CGI and the Children's Psychiatric Rating Scale were the primary outcomes and were reported for both groups.
Other bias	Low risk	Treatment groups did not differ significantly on demographic variables such as age, race, gender, socioeconomic status, severity of illness, or level of cognitive functioning.