[1] Univ Naples Federico II, Pediat Surg Units, I-80131 Naples, Italy
[2] Hop Robert Debre, Pediat Surg Units, F-75019 Paris, France
[3] Juntendo Univ, Pediat Surg Units, Tokyo, Japan
[4] Children Hosp, Pediat Surg Units, Denver, CO USA
[5] Children Hosp, Pediat Surg Units, Buenos Aires, DF, Argentina
[6] Univ Buenos Aires, Pediat Surg Units, Buenos Aires, DF, Argentina
[7] Univ Padua, Pediat Surg Units, Padua, Italy
[8] Padua Hosp, Pediat Surg Units, Padua, Italy
[9] Gaslini Hosp, Pediat Surg Units, Genoa, Italy
[10] Hop Enfants La Timone, Pediat Surg Units, Marseille, France
[11] Aghia Sophia Hosp, Pediat Surg Units, Athens, Greece
[12] Hop Bicetre, Pediat Surg Units, Paris, France
[13] Univ Naples 2, Pediat Surg Units, Naples, Italy
[14] Children Hosp, Pediat Surg Units, Graz, Austria
[15] Univ Perugia, Pediat Surg Units, I-06100 Perugia, Italy
[16] Children Hosp, Pediat Surg Units, Luxembourg, Luxembourg
[17] CHU St Etienne, Pediat Surg Units, St Etienne, France
[18] CHU Tours, Pediat Surg Units, Tours, France
[19] Providence Univ, Pediat Surg Units, Providence, RI USA
[20] Univ Pavia, Pediat Surg Units, I-27100 Pavia, Italy
[21] Univ Strasbourg, Pediat Surg Units, Strasbourg, France
[22] Children Hosp NHS Leeds, Pediat Surg Units, Leeds, W Yorkshire, England
[23] Johannes Gutenberg Univ Mainz, Pediat Surg Units, D-55122 Mainz, Germany