Methods	Allocation: random, no further details. Blindness: single, rater-blinded. Duration: 6 weeks. Design: parallel. Location: single centre.
Participants	Diagnosis: (DSM-IV) schizophrenia. N=56. Sex: 24 M, 29 F (3 not reported) Age: 19-46 years (mean clozapine = 31.3 years, mean olanzapine = 29.6 years, mean quetiapine = 30.1 years, mean risperidone = 27.9 years, mean control group = 32.1 years). History: duration ill mean clozapine = 6.6 years, mean olanzapine = 6.3 years, mean quetiapine = 5.9 years, mean risperidone = 5.6, age at onset: not reported
Interventions	Clozapine: flexible dose. Allowed dose range: not reported. Mean dose: 207.1 mg/day. N = 14. Olanzapine: flexible dose. Allowed dose range: not reported. Mean dose: 15.7 mg/day. N = 14. Quetiapine: flexible dose. Allowed dose range: not reported. Mean dose: 535.7 mg/day. N = 14. Risperidone: flexible dose. Allowed dose range: not reported. Mean dose: 6.7 mg/day. N= 14
Outcomes	Leaving the study early: any reason. Mental State: PANSS total score. Adverse effects: EPS (use of antiparkinson medication), weight gain (BMI), laboratory (serum leptin, triglyceride levels)
Notes
Risk of bias
Bias	Authors’ judgement	Support for judgement
Adequate sequence generation?	Unclear risk	Random, no further details.
Allocation concealment?	Unclear risk	No further details.
Blinding? subjective outcomes	Unclear risk	Single, rater-blind. Whether blinding was successful has not been examined, but the compounds differ quite substantially in side effects. This can be a problem for blinding
Blinding? objective outcomes	Low risk	Objective outcomes such as laboratory measures or death are unlikely to have been much affected by problems of blinding
Incomplete outcome data addressed? All outcomes	Low risk	Three subjects in the control groups left the study early (5.4%). Reason for dropout were not assessed, only completer data were presented. But due to the very low rate we do not think that there was a risk of bias
Free of selective reporting?	Low risk	Probably free of bias. The study focused on serum leptin and triglyceride levels which were adequately described
Free of other bias?	Unclear risk	Data on the allowed dose range have not been presented. Furthermore, the pre-study treatment was quite heterogeneous as 19 participants had never taken any psy-chotropic drugs while most other participants had a long history of previous treatment