1. Faculty of Public Health and Policy, London School of Hygiene and Tropical Medicine, 15-17 Tavistock Place, London WC1H 9SH, UK
2. Luxembourg Institute of Health, 1 A-B Rue Thomas Edison, 1445 Strassen, Luxembourg
3. Luxembourg Institute of Socio-Economic Research, 11 Porte des Sciences, 4366 Esch-sur-Alzette, Luxembourg
4. Centre for Health Economics, University of York, Alcuin ‘A’ Block, University of York, Heslington, York YO10 5DD, UK