Fisher 1956.

Methods	Randomised controlled trial
Participants	22 trauma participants were randomly allocated to 1 of 2 groups: Liberal group: n = 10 Restrictive group: n = 12 NB: no demographic data were reported.
Interventions	In the liberal group, the aim was to achieve 100% or more of the RBC volume at the end of resuscitation. In the restrictive group, an attempt was made to leave the RBC volume at the end of resuscitation at 70% to 80% of normal.
Outcomes	Blood usage (units), blood loss, wound healing, elevated temperature, number of participants transfused, Hb levels
Notes	‐
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	The use of random sequence generation was not described.
Allocation concealment (selection bias)	Unclear risk	The trial used sealed envelopes. When the participant was considered eligible for the trial, they were placed in a severity grade and an envelope was opened to decide which transfusion schedule was to be used.
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Blinding of participants and personnel was not addressed.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Blinding of outcome assessment was not addressed.
Incomplete outcome data (attrition bias) All outcomes	Low risk	The data set appeared to be complete.
Selective reporting (reporting bias)	Low risk	No reporting bias was apparent.
Other bias	Low risk	No other biases were apparent.