[1] Hosp Doctor Josep Trueta, Serv Aparell Digestiu, Girona, Spain
[2] Hosp Manises, Serv Cirugia, Valencia, Spain
[3] Hosp del Mar, Serv Aparato Digest, Barcelona, Spain
[4] Hosp Clin Santiago de Compostela, Serv Aparato Digest, La Coruna, Spain
[5] Hosp Univ Fuenlabrada, Serv Aparato Digest, Madrid, Spain
[6] Hosp Univ 12 Octubre, Serv Aparato Digest, Madrid, Spain
[7] Hosp Badalona Germans Trias & Pujol, Serv Malalties Digest, Barcelona, Spain
[8] Hosp Vall dHebro, Serv Cirugia, Barcelona, Spain
[9] Hosp Univ Mutua Terrassa, Serv Malalties Digest, Barcelona, Spain
[10] CIBERehd, Barcelona, Spain
[11] Hosp Univ Reina Sofia, Serv Aparato Digest, Cordoba, Spain
[12] Hosp Ramon & Cajal, Serv Aparato Digest, E-28034 Madrid, Spain
[13] Hosp Univ 12 Octubre, Serv Digest, Madrid, Spain
[14] Hosp Clin Univ San Carlos, Serv Aparato Digest, Madrid, Spain
[15] Hosp Univ Princesa, CIBERehd, Inst Invest Sanitaria Princesa, Serv Aparato Digest, Madrid, Spain
[16] Hosp Univ Puerta de Hierro, Serv Aparato Digest, Madrid, Spain
[17] Corp Sanitaria Univ Parc Tauli, Hosp Sabadell, Serv Malalties Digest, Catalonia, Spain
[18] Hosp Univ Bellvitge, Serv Malalties Digest, Barcelona, Spain
[19] Complex Hosp Univ Vigo, Serv Ap Dixest, Pontevedra, Spain
[20] Hosp Vall dHebro, Serv Aparato Digest, Barcelona, Spain
[21] Univ Autonoma Barcelona, Dept Med, Inst Univ Parc Tauli, Serv Malaties Digest,Hosp Sabadell, E-08193 Barcelona, Spain
[22] Inst Salud Carlos III, CIBERehd, Madrid, Spain
[23] Hosp Clin Barcelona, Barcelona, Spain
[24] TAISS, Madrid, Spain
[25] Hosp Manises, Serv Aparato Digest, Valencia, Spain
[26] Hosp Univ Burgos, Serv Gastroenterol, Burgos, Spain
[27] Hosp Clin Lozano Blesa Zaragoza, Serv Aparato Digest, Zaragoza, Spain