1 Institute of Applied Health Sciences, Epidemiology Group, School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, Aberdeen AB25 2ZD, UK; Department of Anaesthesia, NHS Grampian, Aberdeen, UK; The European Society of Anaesthesiology and Intensive Care (ESAIC) Pain and Opioids after Surgery (PANDOS) Research Group, Brussels, Belgium. Electronic address: forgetpatrice@yahoo.fr.
2 Department Internal Medicine I, Klinikum Saarbrücken, Saarbrücken, Germany; Department of Psychosomatic Medicine and Psychotherapy, Technische Universität München, Munich, Germany; The European Society of Anaesthesiology and Intensive Care (ESAIC) Pain and Opioids after Surgery (PANDOS) Research Group, Brussels, Belgium.