1. Department of Anaesthesia and Intensive Care Medicine CHU Liège University of Liège Liège Belgium
2. Groupe francophone de réhabilitation améliorée après chirurgie (GRACE; Francophone group for enhanced recovery after surgery) Beaumont France
3. Service of Physical Medicine and Rehabilitation CHU Liège University of Liège Liège Belgium
4. Biostatistics Unit Department of Public Health University of Liège Liège Belgium
5. Service of Digestive Surgery CHU Liège University of Liège Liège Belgium