[1] University of Aberdeen,School of Medicine, Medical Sciences and Nutrition
[2] The University of Texas MD Anderson Cancer Center,Department of Anesthesiology and Perioperative Medicine
[3] Anaesthesiology and Surgical Oncology Research Group,Institute of Applied Health Sciences, Epidemiology Group, School of Medicine, Medical Sciences and Nutrition
[4] University of Aberdeen,undefined
[5] Department of Anaesthesia,undefined
[6] NHS Grampian,undefined