Hébert 1995.

Study characteristics
Methods	Design:  RCT, parallel 2‐arm, multicentre pilot trial Setting: 5 tertiary‐level ICUs, in Canada Recruitment: March 1993 to January 1994 Maximum follow‐up: in‐hospital stay
Participants	69 normovolaemic critically ill participants admitted to 1 of 5 tertiary‐level ICUs with Hb values < 9.0 g/dL within 72 hours of admission were randomly assigned to 1 of 2 groups: Liberal group: n = 36; M/F = 19/17; mean (SD) age = 59 (21) years Restrictive group: n = 33; M/F = 14/19; mean (SD) age = 58 (15) years
Interventions	Liberal group: transfused if Hb fell to between 10.0 g/dL and 10.5 g/dL. Hb maintained between 10.0 g/dL and 12.0 g/dL Restrictive group: transfused if Hb fell to between 7.0 g/dL and 7.5 g/dL. Hb maintained between 7.0 g/dL and 9.0 g/dL
Outcomes	Mortality, length of hospital stay, length of ICU stay, blood usage (units), complications, Hb
Notes	Trial title: Transfusion Requirements in Critical Care (TRICC) Pilot Study Trial registration: none ascertainable Trial funding: this work was supported by the Canadian Red Cross Society, Blood Services, Ottawa, Ontario, and the Physicians' Services Incorporated, North York, Ontario COI statement by investigators: none referred to in published paper
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	"Participants were assigned to 1 of 2 groups by consecutive allocation from a random listing stratified by centre and disease severity ... blocked by balanced groups of 10" (Hébert 1995 p 1440)
Allocation concealment (selection bias)	Unclear risk	Trial reported no information regarding this domain
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'
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	"All randomized patients completed the study" (Hébert 1995 p 1440)
Selective reporting (reporting bias)	Unclear risk	Evidence of prospective registration/trial protocol unavailable; insufficient information available to make a judgement
Other bias	Low risk	No other biases were apparent