Methods	A prospective, randomised study was performed in a tertiary care hospital involving adult patients undergoing elective cardiac valve surgery using cardiopulmonary bypass. Method of randomisation and allocation concealment were not described
Participants	60 patients undergoing cardiac valve surgery were randomised to one of three groups: Group 1 (Autotransfusion group): n=20; M//F=14//6; mean (sd) age = 27.7 (10.1) years Group 2 (Aprotinin group): n=20; M//F=12//8; mean (sd) age = 25.9 (11.1) years Group 3 (Control group): n=20; M//F=12//8; mean (sd) age = 26.6 (7.35) years
Interventions	Group 1: Autotransfusion group patients were treated with cell salvage using a Dideco system before heparin and after protamine administration. Group 2: Aprotinin group patients were treated with aprotinin at the dose of 30, 000KIU/kg added to the pump prime with a further 15,000 KIU/kg added at the end of each hour of CPB. Group 3: Control group patients underwent routine management which included the collection of autologous blood during the pre-CPB period. NB: Groups 1 and 3 had blood remaining in the oxygenator at the conclusion of CPB returned before decannulation or collected in a bag for immediate use to provide optimal filling pressures and hemodynamic stability in the post-CPB period
Outcomes	Outcomes reported: amount of allogeneic blood transfused, re-exploration for bleeding
Notes	Transfusion threshold: bank blood (whole blood) was used in all groups if the haemoglobin level fell below 8.0g/dL
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)	Unclear risk	Method used to conceal treatment allocation was unclear.
Blinding (performance bias and detection bias) All outcomes	High risk