Quetiapine 2009a.

Study characteristics
Methods	Randomisation: randomised (1:1:1 ratio) to bifeprunox, quetiapine or placebo, no further detail. Allocation: procedure not described. Blinding: double‐blind, encapsulated tablets. Duration: 12 weeks. Design: parallel. Location: multi‐centre. Setting: inpatients and outpatients.
Participants	Diagnosis: Schizophrenia (DSM‐IV‐TR), in the maintenance phase (no acute exacerbation and medication unchanged for at least 4 weeks). N = 144. Gender: 78 men, 66 women. Age: 39 years. History: duration stable‐ at least 4 weeks, duration ill‐ n.i., mean duration of hospitalisation‐ n.i., number of previous hospitalisations‐ n.i., age at onset‐ n.i., severity of illness‐ mean PANSS total score 80.2, mean CGI‐S total score 4,2, baseline antipsychotic dose‐ n.i., remission at baseline‐ not in remission (still experiencing clinically significant symptoms, not sufficiently controlled with medication, at least moderately ill at CGI‐S at baseline.
Interventions	1. Drug: Quetiapine. N = 76 Fixed dose. Mean dose: 600 mg/day. 2. Placebo: duration of taper: 21 days, N = 68. Rescue medication: n.i.
Outcomes	Examined Quality of life: Schizophrenia Quality of Life (S‐QoL) scale. Social functioning: Personal and Social Performance scale. Death Unable to use/Not included Relapse (no usable data) Leaving the study early (no usable data, available only for the whole study duration) Global state ‐ number of participants in remission/improved: CGI‐S, CGI‐I (no usable data) Mental state: PANSS total score and subscores (no predefined outcomes of interest) Depressive symptoms: Calgary Depression Scale for Schizophrenia (no predefined outcome of interest) Service use ‐ number of participants hospitalised (no usable data) Social functioning: Global Assessment of Functioning (PSP data used) Adverse effects (no usable data)
Notes	Sponsored by Lundbeck.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Only stated randomised, no further detail.
Allocation concealment (selection bias)	Unclear risk	Procedure not described.
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Double‐blind, encapsulated tablets.
Blinding (performance bias and detection bias) Subjective outcomes	Unclear risk	Double‐blind, encapsulated tablets.
Blinding (performance bias and detection bias) Objective outcomes	Low risk	Double‐blind, encapsulated tablets.
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Global and per‐arm attrition rate are not reported for the randomised placebo‐controlled period, but only for the total duration of the study. Efficacy and safety were assessed on a ITT base.
Selective reporting (reporting bias)	Unclear risk	Relapse was not a pre‐specified outcome. several efficacy outcomes cited as assessed but not reported throughout the text.
Other bias	High risk	Terminated early for negative efficacy results after a pooled interim analysis.