1 From the Institute of Applied Health Sciences, Epidemiology Group, School of Medicine, Medical Sciences and Nutrition, University of Aberdeen (PF); Department of Anaesthesia, NHS Grampian, Aberdeen, UK (PF), Department of Cardiovascular Sciences, KULeuven and Department of Anaesthesiology, UZLeuven, Leuven, Belgium (VdV), University Hospital of Muenster, Muenster, Germany (EP-Z), and Pain AND Opioids After Surgery (PANDOS) European Society of Anaesthesiology and Intensive Care (ESAIC) Research Group, Brussels, Belgium (PF, VdV and EP-Z).