1. Diabetes Trials Unit, Oxford Centre for Diabetes, Endocrinology and MetabolismUniversity of Oxford, Oxford, UK,
2. Department of Public Health, Health Economics Research Centre, University of Oxford, Oxford, UK
3. Department of Public Health, Health Economics Research Centre University of Oxford, Oxford, UK
4. Diabetes Trials Unit, Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Oxford, UK