Authors: Erika Frischknecht Christensen; Mette Dahl Bendtsen; Thomas Mulvad Larsen; Flemming Bøgh Jensen; Tim Alex Lindskou; Hans Ole Holdgaard; Poul Anders Hansen; Søren Paaske Johnsen; Christian Fynbo Christiansen Journal: BMJ Open Date: 2017-08-21 Impact factor: 2.692