1. Newcastle University Medical School, Framlington Place, Newcastle Upon Tyne NE2 4AB, UK
2. Queen Elizabeth Hospital, Sheriff Hill, Gateshead, Tyne & Wear NE9 6SX, UK
3. Teesside University, Middlesbrough, Tees Valley TS1 3BA, UK
4. Newcastle General Hospital, Westgate Road, Newcastle Upon Tyne NE4 6BE, UK