Webert 2008.

Study characteristics
Methods	Design: RCT, parallel 2‐arm, multicentre feasibility study Setting: 4 tertiary haematology centres (Canada) Recruitment: March 2003 to October 2004 Maximum follow‐up: 30 days
Participants	60 adult participants with acute leukaemia were randomly allocated to 1 of 2 groups: Liberal group: n = 31; M/F = 14/17; mean (SD) age = 45.3 (16.8) years Restrictive group: n = 29; M/F = 1811; mean (SD) age = 50.8 (15.3) years
Interventions	Liberal group: transfused with 2 units of RBCs when Hb fell to < 12.0 g/dL Restrictive group: transfused with 2 units of RBCs when Hb dropped to < 8.0 g/dL, with target range of 8.5 g/dL to 9.5 g/dL
Outcomes	Transfusions, bleeding risk, 30‐day mortality provided by trial authors
Notes	Trial registration: none ascertainable Trial funding: "This study was funded by a grant from Canadian Blood Services and a CIHR Canada Research Chair. KEW was supported by a Canadian Blood Services/Novo Nordisk Research Fellowship in Hemostasis. RJC is a Canada Research Chair" (Webert 2008 p 81) COI statement by investigators: no information provided
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Sequence generation was computer generated
Allocation concealment (selection bias)	Low risk	Allocation was Internet based and central
Blinding of participants and personnel (performance bias) Objective outcomes	Low risk	Blinding of personnel for this intervention is not feasible, but in our view, for objective outcomes such as mortality (the primary outcome used within this review), we graded risk of bias as 'low' Participants and clinicians were not blinded
Blinding of outcome assessment (detection bias) Objective measures	Low risk	Blinding of mortality (the primary outcome used within this review) is not relevant, and we graded risk of bias as 'low'
Blinding of outcome assessment (detection bias) Subjective measures	Low risk	No data from subjective outcomes (e.g. function)
Incomplete outcome data (attrition bias) All outcomes	Low risk	No data were missing
Selective reporting (reporting bias)	Unclear risk	No reporting bias was apparent, but in the absence of prospective registration or a trial protocol, assessment must remain 'unclear'
Other bias	Low risk	No other biases were apparent