Comparison 3. Cancer (subgroup: transfusion threshold).

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
3.1 Mortality	2	79	Risk Ratio (M‐H, Random, 95% CI)	0.56 [0.11, 2.80]
3.1.1 No threshold/protocol reported	2	79	Risk Ratio (M‐H, Random, 95% CI)	0.56 [0.11, 2.80]
3.2 Blood loss (mL)	1		Mean Difference (IV, Random, 95% CI)	Totals not selected
3.2.1 No threshold/protocol reported	1		Mean Difference (IV, Random, 95% CI)	Totals not selected
3.3 Infection	1		Risk Ratio (M‐H, Random, 95% CI)	Totals not selected
3.3.1 No threshold/protocol reported	1		Risk Ratio (M‐H, Random, 95% CI)	Totals not selected
3.4 Deep vein thrombosis (DVT)	1		Risk Ratio (M‐H, Random, 95% CI)	Totals not selected
3.4.1 No threshold/protocol reported	1		Risk Ratio (M‐H, Random, 95% CI)	Totals not selected