Methods	Method of randomisation was not reported and allocation concealment was unclear. Baseline comparability was unclear. However the study reported that, “no significant difference between groups were detected at any stage of the study.” Participants were not blind to treatment allocation and blinding of the outcome assessor was unclear [Russian article]
Participants	66 patients undergoing elective coronary artery bypass surgery (CABG) were randomly allocated to one of two groups: Group 1 (Autotransfusion group): n=33 Group 2 (Control group): n=33 NB: Demographic data not reported. Inclusion criteria: patients with an uneventful postoperative period (discharge of less than 800mls through draining tubes during first 8 hours post operation)
Interventions	Group 1: Autotransfusion group had drainage discharge collected for 8 hours post-operatively and reinfused using a BRAT-2 Cell Saver. Drainage discharge collected for 8 hours post-operatively and erythrocytes reinfused post-operatively after washing. The volume of autologous blood collected was up to 800mls. Group 2: Control group received no retransfusion of drainage discharge.
Outcomes	Outcomes reported: number of patients transfused allogeneic blood.
Notes	Transfusion threshold: transfusion protocol not reported. Russian study. English abstract only
Risk of bias
Bias	Authors’ judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Method used to generate allocation sequences was not described
Allocation concealment (selection bias)	High risk	Allocation concealment was not used.
Blinding (performance bias and detection bias) All outcomes	High risk