1. University of Aberdeen; c/o Section of Population Health; Polwarth Building Foresterhill Aberdeen UK AB25 2ZD
2. Queen Elizabeth Hospital; General Surgery; Sheriff Hill Gateshead UK NE9 6SX
3. Aberdeen Royal Infirmary; Ward 31; Aberdeen UK AB25 2ZN
4. University of Warwick; Warwick Clinical Trials Unit; Gibbet Hill Rd Coventry UK CV4 7AL