1. Rigshospitalet; Head and Orthopaedic Center; HOC 2101, Rigshospitalet University of Copenhagen,Blegdamsvej 9 Copenhagen Denmark DK-2100
2. University of Liverpool; Liverpool Reviews and Implementation Group; Second Floor Whelan Building, The Quadrangle, Brownlow Hill Liverpool UK L69 3GB
3. Rigshospitalet; The Cochrane Anaesthesia Review Group; Blegdamsvej 9, Afsnit 5211, rum 1204 Copenhagen Denmark 2100
4. University of Copenhagen Herlev Hospital; The Cochrane Anaesthesia Review Group, Rigshospitalet & Department of Anaesthesiology; Herlev Ringvej Herlev Denmark 2730
5. Royal Lancaster Infirmary; Department of Anaesthetics; Ashton Road Lancaster Lancashire UK LA1 4RP
6. Royal Lancaster Infirmary; Patient Safety Research; Pointer Court 1, Ashton Road Lancaster UK LA1 1RP