1. Countess of Chester NHS Foundation Trust, Chester CH2 1UK, UK
2. College of Emergency Medicine, Ultrasound Subcommittee (Chair – J Sloan), Churchill House, London WC1R 4SJ, UK
3. Gateshead Health NHS Foundation Trust, Gateshead NE9 6SX, UK
4. Teesside University, Middlesbrough TS1 3BA, UK