1. Royal Lancaster Infirmary; Lancaster Patient Safety Research Unit; Pointer Court 1, Ashton Road Lancaster UK LA1 4RP
2. Royal Lancaster Infirmary; Department of Anaesthesia; Ashton Road Lancaster Lancashire UK LA1 4RP
3. NHS Greater Glasgow and Clyde/University of Glasgow; Glasgow Royal Infirmary (North Sector); Glasgow UK
4. National Institute for Health and Care Excellence; Level 1A, City Tower, Piccadilly Plaza Manchester UK M1 4BD