Blair 1986.

Methods	Randomised controlled trial
Participants	50 consecutive participants with severe upper gastrointestinal haemorrhage were randomized to 1 of 2 groups: Liberal group: n = 24; mean (SD) age = 64 (17.6) years Restrictive group: n = 26; mean (SD) age = 60 (17.8) years
Interventions	The liberal group received at least 2 units of red blood cells immediately at admission and during their first 24 hours in hospital. The restrictive group were not transfused red blood cells unless the Hb was less than 8.0 g/dL or shock persisted after initial resuscitation with Haemaccel.
Outcomes	Blood usage (units), rebleeding, mortality, clotting times, Hct on admission/discharge, kaolin cephalin clotting time after 24 hours, impedance clotting time after 24 hours
Notes	‐
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	The trial reported no information regarding this domain.
Allocation concealment (selection bias)	Unclear risk	The trial reported no information regarding this domain.
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	The trial reported no information regarding this domain.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	The trial reported no information regarding this domain.
Incomplete outcome data (attrition bias) All outcomes	Low risk	There were no missing data.
Selective reporting (reporting bias)	Low risk	No reporting bias was apparent.
Other bias	Low risk	No other biases identified.