1. Department of Clinical Epidemiology; Aarhus University Hospital; Aarhus Denmark
2. Gillings School of Global Public Health; University of North Carolina; Chapel Hill USA
3. Division of Gastroenterology and Hepatology; Department of Medicine; University of North Carolina School of Medicine; Chapel Hill USA
4. MRC Integrative Epidemiology Unit (IEU); School of Social and Community Medicine; University of Bristol; Bristol UK