Hong 2011.

Methods	RCT, USA. Pts recruited from the community.
Participants	69 pts (43 smokers) with a diagnosis of schizophrenia or schizoaffective disorder. All received antipsychotic medications and they were clinically stable for at least 4 wks. Aged between 18 and 60. Exclusion criteria included: (1) pts were undergoing smoking cessation therapy; (2) major medical conditions; (3) atrioventricular block as identified by ECG; (4) renal insufficiency. Interest in quitting smoking is not required. No TQD set. Among 43 smokers, 27 were males. Mean age 42.2. Average CPD 18.
Interventions	1. Varenicline 0.5mg daily for 1 wk then 0.5mg twice daily for 7 wks (total 8 wks) 2. Placebo for 8 wks Both groups did not receive any additional intervention.
Outcomes	Abstinence not defined or measured. Reduction of smoking measured by reduction of CPD and reduction of the expired CO level. Measurement taken at wk 1, 2, 4, 6, 8 and 10. Effects on mental state measured by BPRS, SANS, HAM‐D and CGI.
Source of funding	Stanley Medical Research Institute, NIH, Neurophysiology Core of the University of Maryland General Clincial Research Centre
Primary aim of the study	Effect of varenicline on neurobiological and cognitive biomarkers in schizophrenia
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	The method of sequence generation was not described.
Allocation concealment (selection bias)	Unclear risk	No description of allocation concealment in the reports.
Blinding (performance bias and detection bias) All outcomes	Unclear risk	Not stated
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Not stated
Selective reporting (reporting bias)	Low risk	All expected outcomes
Other bias	Low risk