1. Clinical Hospital Centre Rijeka; Department of Gastroenterology; Kresimirova 42 Rijeka Croatia 51 000
2. Copenhagen Trial Unit, Centre for Clinical Intervention Research, Department 7812, Rigshospitalet, Copenhagen University Hospital; The Cochrane Hepato-Biliary Group; Department 7812, Rigshospitalet, Copenhagen University Hospital Copenhagen Denmark
3. McMaster University; Department of Clinical Epidemiology and Biostatistics; Hamilton Ontario Canada
4. Faculty of Medicine, Cairo University; Endemic Medicine and Liver Department; Cairo Egypt