1. Longhua Hospital, Shanghai Traditional Chinese Medicine University; Department of Anorectal Surgery; 725 South Wanping Road, Xuhui District Shanghai Shanghai China 200032
2. Zhongshan Hospital, Fudan University; Department of General Surgery, Institute of General Surgery; 180 Fenglin Road, Xuhui District Shanghai Shanghai China 200032
3. Faculty of Medicine, Lund University; Department of Surgery, Clinical Sciences; Lund University Hospital Lund Sweden SE-221 85
4. Systematic Review Solutions Ltd; 5-6 West Tashan Road Yan Tai China 264000