1. Department of Pediatrics Örebro University HospitalÖrebro Sweden
2. Clinical Epidemiology Unit Department of Medicine Karolinska InstitutetStockholm Sweden
3. Division of Epidemiology and Public Health University of Nottingham Nottingham City HospitalNottingham UK
4. Division of Nutritional Sciences King's College London The Rayne Institute LondonLondon UK
5. Department of Gastroenterology Cardiff and Vale University Health BoardCardiff UK
6. Regional GI and Liver Unit Royal Hallamshire HospitalSheffield UK
7. Department of Medicine and Surgery, Gastroenterology University of SalernoSalerno Italy