Ref (type)	Population	Outcome, Interventions	Results and statistical analysis	Effect size	Favours
Wound infection
RCT	735 people aged 14 to 91 years with complicated appendicitis or simple appendicitis	Proportion of people with wound infections 33/374 (8.8%) with double invagination (purse string with Z stitch) 30/361 (8.3%) with simple ligation	P value not reported Reported as not significant		Not significant
RCT	134 people aged 4 to 90 years	Proportion of people with wound infections 4/55 (7%) with double invagination 0/79 (0%) with simple ligation	P = 0.017	Effect size not calculated	simple ligation