García, M. J., Rivero, M., Miranda-Bautista, J., Bastón-Rey, I., Mesonero, F., Leo-Carnerero, E., Casas-Deza, D., Cagigas Fernández, C., Martin-Cardona, A., El Hajra, I., Hernández-Aretxabaleta, N., Pérez-Martínez, I., Fuentes-Valenzuela, E., Jiménez, N., Rubin de Célix, C., Gutiérrez, A., Suárez Ferrer, C., Huguet, J. M., Fernández-Clotet, A., González-Vivó, M., Del Val, B., Castro-Poceiro, J., Melcarne, L., Dueñas, C., Izquierdo, M., Monfort, D., Bouhmidi, A., Ramírez de la Piscina, P., Romero, E., Molina, G., Zorrilla, J., Calvino-Suárez, C., Sánchez, E., Núñez, A., Sierra, O., Castro, B., Zabana, Y., González-Partida, I., De la Maza, S., Castaño, A., Nájera-Muñoz, R., Sánchez-Guillén, L., Riat Castro, M., Rueda, J. L., Benítez, J. M., Delgado-Guillena, P., Tardillo, C., Peña, E., Frago-Larramona, S., Rodríguez-Grau. M. C., Plaza, R., Pérez-Galindo, P., Martínez-Cadilla, J., Menchén, L., Barreiro-De Acosta, M., Sánchez-Aldehuelo, R., De la Cruz, M. D., Lamuela, L. J., Marín, I., Nieto-García, L., López San Román, A., Herrera, J. M., Chaparro, M., Gisbert, J. P., Young Group of GETECCU, [García MJ, Rivero M] Gastroenterology Department, Hospital Universitario Marqués de Valdecilla, Universidad de Cantabria, Instituto de Investigación Sanitaria Valdecilla (IDIVAL), Santander, Spain. [Miranda-Bautista J] Gastroenterology Department, Hospital Universitario Gregorio Marañón, Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM), and Departamento de Medicina, Universidad Complutense, Madrid, Spain. [Bastón-Rey I] Gastroenterology Department, Hospital Universitario Clínico de Santiago, Santiago de Compostela, Spain. [Mesonero F] Gastroenterology Department, Hospital Universitario Ramón y Cajal, Madrid, Spain. [Leo-Carnerero E] Gastroenterology Department, Hospital Universitario Virgen del Rocío, Sevilla, Spain. [Delgado-Guillena P] Gastroenterology Department, Hospital General de Granollers, Granollers, Spain, Hospital General de Granollers, [Jose Garcia, Maria] Univ Cantabria, Hosp Univ Marques de Valdecilla, Inst Invest Sanitaria Valdecilla IDIVAL, Gastroenterol Dept, Santander 37008, Spain, [Rivero, Montserrat] Univ Cantabria, Hosp Univ Marques de Valdecilla, Inst Invest Sanitaria Valdecilla IDIVAL, Gastroenterol Dept, Santander 37008, Spain, [Castro, Beatriz] Univ Cantabria, Hosp Univ Marques de Valdecilla, Inst Invest Sanitaria Valdecilla IDIVAL, Gastroenterol Dept, Santander 37008, Spain, [Miranda-Bautista, Jose] Univ Complutense, Hosp Univ Gregorio Maranon, Inst Invest Sanitaria Gregorio Maranon IiSGM, Gastroenterol Dept, Madrid 28009, Spain, [Menchen, Luis] Univ Complutense, Hosp Univ Gregorio Maranon, Inst Invest Sanitaria Gregorio Maranon IiSGM, Gastroenterol Dept, Madrid 28009, Spain, [Marin, Ignacio] Univ Complutense, Hosp Univ Gregorio Maranon, Inst Invest Sanitaria Gregorio Maranon IiSGM, Gastroenterol Dept, Madrid 28009, Spain, [Miranda-Bautista, Jose] Univ Complutense, Dept Med, Madrid 28009, Spain, [Menchen, Luis] Univ Complutense, Dept Med, Madrid 28009, Spain, [Marin, Ignacio] Univ Complutense, Dept Med, Madrid 28009, Spain, [Baston-Rey, Iria] Hosp Univ Clin Santiago, Gastroenterol Dept, Santiago De Compostela 15706, Spain, [Calvino-Suarez, Cristina] Hosp Univ Clin Santiago, Gastroenterol Dept, Santiago De Compostela 15706, Spain, [Barreiro-De Acosta, Manuel] Hosp Univ Clin Santiago, Gastroenterol Dept, Santiago De Compostela 15706, Spain, [Nieto-Garcia, Laura] Hosp Univ Clin Santiago, Gastroenterol Dept, Santiago De Compostela 15706, Spain, [Mesonero, Francisco] Hosp Univ Ramon y Cajal, Gastroenterol Dept, Madrid 28034, Spain, [Sanchez, Eugenia] Hosp Univ Ramon y Cajal, Gastroenterol Dept, Madrid 28034, Spain, [Sanchez-Aldehuelo, Ruben] Hosp Univ Ramon y Cajal, Gastroenterol Dept, Madrid 28034, Spain, [Lopez-San Roman, Antonio] Hosp Univ Ramon y Cajal, Gastroenterol Dept, Madrid 28034, Spain, [Leo-Carnerero, Eduardo] Hosp Univ Virgen del Rocio, Gastroenterol Dept, Seville 41013, Spain, [Nunez, Andrea] Hosp Univ Virgen del Rocio, Gastroenterol Dept, Seville 41013, Spain, [Dolores De la Cruz, Maria] Hosp Univ Virgen del Rocio, Gastroenterol Dept, Seville 41013, Spain, [Manuel Herrera, Jose] Hosp Univ Virgen del Rocio, Gastroenterol Dept, Seville 41013, Spain, [Casas-Deza, Diego] Hosp Univ Miguel Servet, Inst Invest Sanitaria Aragon IISA, Gastroenterol Dept, Zaragoza 50009, Spain, [Sierra, Olivia] Hosp Univ Miguel Servet, Inst Invest Sanitaria Aragon IISA, Gastroenterol Dept, Zaragoza 50009, Spain, [Javier Lamuela, Luis] Hosp Univ Miguel Servet, Inst Invest Sanitaria Aragon IISA, Gastroenterol Dept, Zaragoza 50009, Spain, [Cagigas Fernandez, Carmen] Hosp Univ Marques de Valdecilla, Dept Gen & Digest Surg, Colorectal Unit, Santander 39008, Spain, [Martin-Cardona, Albert] Hosp Univ Mutua Terrassa, Ctr Invest Biomed Red Enfermedades Hepat & Digest, Gastroenterol Dept, Terrassa 08221, Spain, [Zabana, Yamile] Hosp Univ Mutua Terrassa, Ctr Invest Biomed Red Enfermedades Hepat & Digest, Gastroenterol Dept, Terrassa 08221, Spain, [El Hajra, Ismael] Hosp Univ Puerta de Hierro, Gastroenterol Dept, Majadahonda 28220, Spain, [Gonzalez-Partida, Irene] Hosp Univ Puerta de Hierro, Gastroenterol Dept, Majadahonda 28220, Spain, [Hernandez-Aretxabaleta, Nerea] Hosp Univ Basurto, Gastroenterol Dept, Bilbao 48013, Spain, [De la Maza, Saioa] Hosp Univ Basurto, Gastroenterol Dept, Bilbao 48013, Spain, [Perez-Martinez, Isabel] Hosp Univ Cent Asturias, Inst Invest Sanitaria Principado Asturias ISPA 33, Dept Gastroenterol, Oviedo 33011, Spain, [Castano, Andres] Hosp Univ Cent Asturias, Inst Invest Sanitaria Principado Asturias ISPA 33, Dept Gastroenterol, Oviedo 33011, Spain, [Fuentes-Valenzuela, Esteban] Hosp Univ Rio Hortega, Gastroenterol Dept, Valladolid 47012, Spain, [Najera-Munoz, Rodrigo] Hosp Univ Rio Hortega, Gastroenterol Dept, Valladolid 47012, Spain, [Jimenez, Nuria] Hosp Gen Univ Elche, Gastroenterol Dept, Alicante 03203, Spain, [Rubin de Celix, Cristina] Univ Autonoma Madrid UAM, Gastroenterol Dept, Hosp Univ La Princesa, Inst Invest Sanitaria Princesa IIS IP,Ctr Invest, Madrid 28006, Spain, [Castro, Micaela Riat] Univ Autonoma Madrid UAM, Gastroenterol Dept, Hosp Univ La Princesa, Inst Invest Sanitaria Princesa IIS IP,Ctr Invest, Madrid 28006, Spain, [Chaparro, Maria] Univ Autonoma Madrid UAM, Gastroenterol Dept, Hosp Univ La Princesa, Inst Invest Sanitaria Princesa IIS IP,Ctr Invest, Madrid 28006, Spain, [Gisbert, Javier P.] Univ Autonoma Madrid UAM, Gastroenterol Dept, Hosp Univ La Princesa, Inst Invest Sanitaria Princesa IIS IP,Ctr Invest, Madrid 28006, Spain, [Gutierrez, Ana] Hosp Gen Alicante, Gastroenterol Dept, Ctr Invest Biomed Red Enfermedades Hepat & Digest, Inst Invest Sanitaria & Biomed Alicante ISABIAL, Alicante 03010, Spain, [Suarez Ferrer, Cristina] Hosp Univ La Paz, Gastroenterol Dept, Madrid 28046, Spain, [Luis Rueda, Jose] Hosp Univ La Paz, Gastroenterol Dept, Madrid 28046, Spain, [Maria Huguet, Jose] Hosp Gen Univ Valencia, Gastroenterol Dept, Valencia 46014, Spain, [Fernandez-Clotet, Agnes] Hosp Clin Barcelona, Gastroenterol Dept, Barcelona 08036, Spain, [Gonzalez-Vivo, Maria] Hosp del Mar, Gastroenterol Dept, Barcelona 08003, Spain, [Del Val, Blanca] Hosp Rafael Mendez, Gastroenterol Dept, Lorca 30817, Spain, [Castro-Poceiro, Jesus] Hosp St Joan Despi Moises Broggi, Gastroenterol Dept, Barcelona 08970, Spain, [Melcarne, Luigi] Hosp Univ Parc Tauli, Gastroenterol Dept, Sabadell, Ctr Invest Biomed Red Enfermedades Hepat & Digest, Barcelona 08208, Spain, [Duenas, Carmen] Hosp Univ Caceres, Gastroenterol Dept, Caceres 10003, Spain, [Izquierdo, Marta] Hosp Univ Cabuenes, Gastroenterol Dept, Gijon 33203, Spain, [Monfort, David] Consorcio Sanitario Terrasa, Gastroenterol Dept, Barcelona 08227, Spain, [Bouhmidi, Abdel] Hosp Santa Barbara, Gastroenterol Dept, Puertollano 13500, Spain, [Ramirez De la Piscina, Patricia] Hosp Univ Vitoria Gasteiz, Gastroenterol Dept, Vitoria 01002, Spain, [Romero, Eva] Hosp Clin Univ Valencia, Gastroenterol Dept, Valencia 46010, Spain, [Molina, Gema] Hosp Arquitecto Marcide, Gastroenterol Dept, Ferrol 15405, Spain, [Zorrilla, Jaime] Hosp Univ Gregorio Maranon, Dept Colorectal & Gastrointestinal Surg, Madrid 28009, Spain, [Sanchez-Guillen, Luis] Hosp Gen Univ Elche, Dept Colorectal & Gastrointestinal Surg, Alicante 03203, Spain, [Manuel Benitez, Jose] Hosp Reina Sofia, Gastroenterol Dept, IMIBIC, Cordoba 14004, Spain, [Delgado-Guillena, Pedro] Hosp Gen Granollers, Gastroenterol Dept, Granollers 08042, Spain, [Tardillo, Carlos] Hosp Nuestra Sanora de la Candelaria, Gastroenterol Dept, Tenerife 38010, Spain, [Pena, Elena] Hosp Royo Villanova, Gastroenterol Dept, Zaragoza 50007, Spain, [Frago-Larramona, Santiago] Complejo Hosp Soria, Gastroenterol Dept, Soria 42005, Spain, [Carmen Rodriguez-Grau, Maria] Hosp Univ Henares, Gastroenterol Dept, Coslada 28002, Spain, [Plaza, Rocio] Hosp Univ Infanta Leonor, Gastroenterol Dept, Madrid 28031, Spain, [Perez-Galindo, Pablo] Complejo Hosp Univ Pontevedra, Gastroenterol Dept, Pontevedra 36071, Spain, [Martinez-Cadilla, Jesus] Hosp Alvaro Cunqueiro Vigo, Gastroenterol Dept, Vigo 36312, Spain, and Spanish Working Group in Crohn's Disease and Ulcerative Colitis (GETECCU)