Estrid Muff Munk1
, Bente Nørgård2
, Claus Dethlefsen3
, Hans Gregersen4
, Asbjørn Mohr Drewes4
, Peter Funch-Jensen5
and Henrik Toft Sørensen1 
1Department of Clinical Epidemiology, Aarhus and Aalborg Hospital, Aarhus, University Hospital, DK-8000 Aarhus C, Denmark
2Department of Clinical Epidemiology, Aarhus University Hospital, DK-8000 Aarhus C, and Department of Applied Research and Health Technology Assessment, Odense University Hospital, DK-5000 Odense C. Denmark
3Center for Cardiovascular Research, Aalborg Hospital, Aarhus University, Hospital, DK-9000 Aalborg, Denmark
4Center of Visceral Biomechanics and Pain, Department of Gastroenterology, Aalborg Hospital, Aarhus University Hospital, DK-9000 Aalborg, Denmark
5Department of Surgical Gastroenterology L, Aarhus Hospital, Aarhus University, Hospital, DK-8000 Aarhus C, Denmark