[1] Gregorio Maranon Univ Gen Hosp, Dept Pediat Surg, Calle Dr Esquerdo 46, Madrid 28007, Spain
[2] Tel Aviv Univ, Sackler Med Sch, Schneider Childrens Med Ctr Israel, Dept Pediat Surg, Tel Aviv, Israel
[3] Bambino Gesu Pediat Hosp, Dept Med & Surg Neonatol, Rome, Italy
[4] Fdn Ca Granda Osped Maggiore Policlin, Dept Pediat Surg, Milan, Italy
[5] Erasmus MC Sophia Childrens Hosp, Dept Pediat Surg, Rotterdam, Netherlands
[6] Vall dHebron Hosp, Dept Pediat Surg, Barcelona, Spain
[7] Italian Assoc Anorectal Malformat, Rome, Italy
[8] Ca Foncello Hosp, Sect Pediat Surg, Mother & Child Dept, Treviso, Italy