1. Department of Gastroenterology, University Hospital of North Staffordshire, Stoke-on-Trent, UK
2. Centre for Health Planning and Management, Keele University, Keele, UK
3. Department of Dietetics, Chelsea and Westminster Hospital, London, UK
4. Department of Gastroenterology and Nutrition, Central Middlesex Hospital, London, UK
5. Nutricia Clinical Care, Trowbridge, UK
6. Department of Mathematics, Keele University, Keele, UK