Comparison 2. Direct estimation using calibrated drapes versus gravimetric technique.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Blood loss greater than 500 mL	1	900	Risk Ratio (M‐H, Fixed, 95% CI)	1.86 [1.11, 3.11]
2 Blood transfusion	1	900	Risk Ratio (M‐H, Fixed, 95% CI)	1.0 [0.06, 15.94]
3 Use of plasma expanders	1	900	Risk Ratio (M‐H, Fixed, 95% CI)	0.67 [0.19, 2.35]
4 Use of therapeutic uterotonics	1	900	Risk Ratio (M‐H, Fixed, 95% CI)	1.01 [0.90, 1.13]
5 Further operative procedures (composite)	1	900	Risk Ratio (M‐H, Fixed, 95% CI)	0.6 [0.14, 2.50]
6 Further operative procedures (manual removal of the placenta)	1	900	Risk Ratio (M‐H, Fixed, 95% CI)	0.5 [0.09, 2.72]
7 Further operative procedures (surgical procedures or embolization)	1	900	Risk Ratio (M‐H, Fixed, 95% CI)	1.0 [0.06, 15.94]
8 Mean change in Hb	1	781	Mean Difference (IV, Fixed, 95% CI)	‐0.10 [‐0.30, 0.10]