B +quet/risp 2009.

Methods	Allocation: randomised. Blinding: double‐blind. Duration: 16 weeks. Setting: outpatients. Design: parallel. Country: USA, multi‐centre.
Participants	Diagnosis: schizophrenia or schizoaffective disorder (DSM‐IV‐TR). N = 323 Sex: M 198, F 125. Age: average ˜ 44 years. History: chronic, stable. Currently receiving a stable dose of quetiapine (400‐800 mg/d) or risperidone (4 mg to 8 mg/day) for ≥4 weeks but with an inadequate response; must not have shown significant improvement or worsening of symptoms within 1 month of screening.
Interventions	Combination therapy: aripiprazole + quetiapine (N = 78). Combination therapy: aripiprazole + risperidone (N = 90). Monotherapy: quetiapine + placebo (N = 68). Monotherapy: risperidone + placebo (N = 87). Schedule: aripiprazole 2‐15 mg/d, quetiapine 400 mg to 800 mg/day, risperidone 4 mg to 8 mg/day.
Outcomes	‐ Usable data ‐ Leaving the study early. Clinical response: not clinically improved. Mental state: PANSS positive and PANSS negative. Adverse events: serious or requiring discontinuation, weight gain, movement disorders, deaths. ‐ Unable to use ‐ Global state: CGI (no SDs reported, no suitable mean to impute data). Mental state: PANSS total score, MADRS (no SDs reported, no suitable mean to impute data). Adverse events: AIMS, SAS, BAS, average weight gain, prolactin (no SDs reported, no suitable mean to impute data). Quality of life: SWN (no SDs reported, no suitable mean to impute data). ‐ Not used in review ‐ Calgary Depression Scale for Schizophrenia (CDSS), Arizona Sexual Experience Scale (ASEX), Fatigue Symptom Inventory (FSI), Brief Assessment of cognition in schizophrenia (BACS), Investigator’s Assessment Questionnaire (IAQ), HDL, LDL, fasting glucose, triglycerides.
Notes	Trial Registration: clinicaltrials.cog Identifier: NCT00325689
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	No details provided.
Allocation concealment (selection bias)	Unclear risk	No details provided.
Blinding (performance bias and detection bias) All outcomes	Unclear risk	No details provided.
Incomplete outcome data (attrition bias) All outcomes	Low risk	All patients were analysed for safety. For efficacy analysis LOCF method was used.
Selective reporting (reporting bias)	Low risk	All expected outcomes reported.
Other bias	High risk	Supported by Bristol‐Mywers Squibb (USA) and Otsuka Pharmaceutical Co (Japan)