2. Assessment and grading of bleeding.

Study	Bleeding primary outcome of study	Method of bleeding assessment reported	Bleeding severity scale used	RBC usage part of bleeding severity assessment	RBC transfusion policy
Rebulla 1997	Yes	Yes	New scale developed by Rebulla	Yes	Haemoglobin < 80 g/L
Heckman 1997	Not reported	Yes	Ajani 1990	Yes	Not reported
Diedrich 2005	No	Yes	WHO 1979	No	Haemoglobin < 80 g/L

RBC = red blood cell