1. Endoscopy Unit Gastroenterology Department ICMDM, CIBEREHD, IDIBAPS, Hospital Clínic University of Barcelona Barcelona Spain
2. Endoscopy Unit Gastroenterology Department “i+12 Research Institute”, Hospital Universitario 12 de Octubre Universidad Complutense Madrid Spain
3. Endoscopy Unit Gastroenterology Department IDIPHISA, Hospital Universitario Puerta de Hierro Autonomous University of Madrid Madrid Spain
4. Complejo Hospitalario de Navarra, Navarrabiomed Biomedical Research Center UPNA IdiSNA Pamplona Spain
5. Hospital Gregorio Marañón Marañón, Madrid Spain
6. Hospital Quirón Málaga Spain
7. Hospital Universitario de Donostia San Sebastián Spain
8. Centro Médico Teknon, Barcelona Barcelona Spain
9. Hospital Universitario Marqués de Valdecilla Santander Spain
10. Complejo Universitario de Salamanca Salamanca Spain
11. Hospital General Universitario de Ciudad Real Ciudad Real Spain