1. Coventry University; Centre for Technology Enabled Health Research (CTEHR); Priory Street Coventry UK CV1 5FB
2. Copenhagen Trial Unit, Centre for Clinical Intervention Research, Department 7812, Rigshospitalet, Copenhagen University Hospital; Cochrane Hepato-Biliary Group; Blegdamsvej 9 Copenhagen Denmark DK-2100
3. Gentofte University Hospital; Department F, Gastroenterology Section; Niels Andersensvej 65 Hellerup Denmark 2900
4. Copenhagen University Hospital Hvidovre; Gastrounit, Medical Division; Kettegaards Alle Hvidovre Denmark 2650