1 From the Department of Anaesthesiology and Intensive Care Medicine, St. Josef Hospital, University Hospital, Ruhr University of Bochum, Bochum (MB); Department of Anaesthesiology, Intensive Care Medicine and Pain Medicine, Saarland University Medical Centre, Homburg, Saarland (HB, AM); and Institute for Medical Biometry, Epidemiology and Medical Informatics, Campus Homburg, Saarland University, Homburg, Germany (SW).