Affiliation: | 1. Department of Anaesthesiology and Pain Management, Rijnstate Hospital, Arnhem, the Netherlands;2. Department of Anaesthesiology and Pain Medicine, Maastricht University Medical Centre, Maastricht, the Netherlands;3. Department of Clinical Epidemiology and Medical Technology, Maastricht University Medical Centre, Maastricht, the Netherlands;4. Department of Orthopaedic Surgery, Maastricht University Medical Centre, Maastricht, the Netherlands;5. Department of Neurosurgery, Maastricht University Medical Centre, Maastricht, the Netherlands;6. Department of Neurosurgery, Atrium Medisch Centrum Heerlen, Heerlen, the Netherlands |