1. Department of Endoscopy, Mediterraneo Hospital, Glyfada, Athens, Greece;
2. Department of Gastroenterology, Vivantes-Friedrichshain Hospital, Berlin, Germany;
3. Department of Hepatogastroenterology, Cliniques Universitaires Saint-Luc, Université Catholique de Louvain, Brussels, Belgium;
4. Department of Endoscopy, Internal Medicin Clinic, Sahlgrenska University Hospital/East Hospital, Gothenburg, Sweden;
5. Department of Gastroenterology, Clinique Saint Barbe, Strasbourg, France;
6. Department of Gastroenterology, Japan Community Healthcare Organization Osaka Hospital, Fukushima, Osaka, Japan