Ref (type)	Population	Outcome, Interventions	Results and statistical analysis	Effect size	Favours
Adverse effects
Systematic review	184 people, approximately (150 men, 34 women), mean age range 43 to 47 years 4 RCTs in this analysis	Proportion of people with postoperative morbidity 40/91 (44%) with pancreaticoduodenectomy 23/93 (25%) with duodenum-preserving pancreatic head resection	RR 0.54 95% CI 0.20 to 1.46 P = 0.22		Not significant
Systematic review	184 people, approximately (150 men, 34 women), mean age range 43 to 47 years 4 RCTs in this analysis	Intraoperative blood replacement with pancreaticoduodenectomy with duodenum-preserving pancreatic head resection Absolute numbers not reported	WMD –1.28 units 95% CI –2.32 units to –0.25 units P = 0.02	Moderate effect size	duodenum-preserving pancreatic head resection