Chapter 1: Burden of Digestive Disorders Rasmussen et al. 201581 Zito et al. 201582 Chirila et al. 201683 Ebling et al. 201684 Palsson et al. 201685 Aziz et al. 201886 Pereira et al. 201687 Wensaas et al. 201688 Denmark Italy Romania Croatia UK UK Portugal Norway Belgium Egypt France Germany Netherlands Israel Italy Sperber et al. 202189 Poland Romania Russia Spain Sweden Turkey UK Turkey Self-completed online questionnaire Questionnaire, type not reported Interview-administered questionnaire Self-completed postal questionnaire Self-completed online questionnaire Self-completed online questionnaire Self-completed paper questionnaire provided at an appointment Self-completed postal questionnaire Self-completed online questionnaire Self-completed online questionnaire Self-completed online questionnaire Self-completed online questionnaire Self-completed online questionnaire Self-completed online questionnaire Self-completed online questionnaire Self-completed online questionnaire Self-completed online questionnaire Self-completed online questionnaire Self-completed online questionnaire Self-completed online questionnaire Self-completed online questionnaire Self-completed online questionnaire Interview-administered questionnaire Rome III (defined as per Rome) Rome III (defined as per Rome) Rome III (not reported) Rome III (defined as per Rome) Rome III (defined as per Rome) Rome IV (defined as per Rome) Rome III (defined as per Rome) Rome III (defined as per Rome) Rome IV (defined as per Rome) Rome IV (defined as per Rome) Rome IV (defined as per Rome) Rome IV (defined as per Rome) Rome IV (defined as per Rome) Rome IV (defined as per Rome) Rome IV (defined as per Rome) Rome IV (defined as per Rome) Rome IV (defined as per Rome) Rome IV (defined as per Rome) Rome IV (defined as per Rome) Rome IV (defined as per Rome) Rome IV (defined as per Rome) Rome IV (defined as per Rome) Rome IV (defined as per Rome) Data source: Barberio et al.68 Table shows studies conducted in UEG member countries. 47884 1134 184 663 1994 1994 166 1049 2021 2020 2019 2020 2008 2012 2063 2057 2049 2000 2072 2084 2010 2027 1950 3668 (7.7) 243 (21.4) 14 (7.6) 110 (16.6) 118 (5.9) 152 (7.6) 67 (40.4) 72 (6.9) 101 (5.0) 248 (12.3) 172 (8.5) 139 (6.9) 82 (4.1) 72 (3.6) 188 (9.1) 171 (8.3) 152 (7.4) 206 (10.3) 153 (7.4) 171 (8.2) 107 (5.3) 134 (6.6) 21 (1.1) White Book 2: Part 1 104