Potkin 2006.

Methods	Allocation: randomised. Blindness: double. Duration: 6 weeks*. Setting: inpatients, 30 sites, USA. Design: parallel.
Participants	Diagnosis: schizophrenia or schizoaffective disorder (DSM‐IV). N = 381. Age: mean ˜ 34.8 years, SD ˜ 9.7 years. Sex: male = 228 and female = 153. Length of illness: not reported. Inclusion criteria: 18‐64 years old, acute exacerbation of schizophrenia of recent onset (within 4 weeks), have a score of ≥ 4 at least 2 of the following items on the PANSS: Hostility, Excitment, Tension, Uncooperativeness, and Poor Impulse Control, and a total score on the 5 items of at least 17, CGI ≥ 5. Exclusion criteria: comorbid Axis 1 diagnosis with the exception of substance abuse/dependence, borderline personality disorder, mental retardation or clinically significant medical illness, also excluded were people who received risperidone or quetiapine within 7 days of baseline, clozapine within 60 days, or depot antipsychotic or electroconvulsive therapy within the study period.
Interventions	1. Risperidone: dose 4.7 ± 0.9 mg/day, N = 153. 2. Quetiapine: dose 579.5 ± 128.9 mg/day, N = 156. 3. Placebo: N = 73. Zolpidem, zopiclone, and zaleplon used to treat insomnia. Injectable lorazepam, sodium amytal, or midazolam used for treating agitation or restlessness. Benztropine mesylate or an equivalent treatment for movement disorder was permitted throughout study as needed.
Outcomes	Mental state: PANSS. Leaving the study early. Global state: CGI‐Severity, CGI‐Change. Adverse effects: SAS, BAS, prolactin, EPS. Unable to use: Readiness for discharge questionnaire (not a validated scale). Study medication satisfaction (not a validated scale).
Notes	*2 weeks monotherapy phase followed by a 4‐week additive therapy phase. In the additive therapy phase, all the participants in the 3 groups received other antipsychotic drugs. As the data in these two phases is reported separately, we only use the data from the 2‐week monotherapy phase.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Randomised using a centralised interactive voice response system. Quote: "A non‐centralised randomisation strategy was used to ensure that subjects were balanced across the three treatments within each investigate site... subjects were assigned to a double blind treatment using a centralized interactive voice response system (IVRS)" (p255)
Allocation concealment (selection bias)	Low risk	Concealed with centralised IVRS.
Blinding (performance bias and detection bias) All outcomes	Low risk	Double blind by using a centralised IVRS (p255)
Incomplete outcome data (attrition bias) All outcomes	Low risk	ITT analysis was used.
Selective reporting (reporting bias)	Low risk	All outcomes measured were reported.
Other bias	High risk	Supported by Janssen Pharmaceutica.