1. MRC Centre for Environment and Health, School of Public Health Imperial College London London UK
2. Centre for Health Economics & Policy Innovation (CHEPI), Imperial College Business School, and School of Public Health Imperial College London London UK
3. Research Group on Statistics, Econometrics and Health (GRECS) University of Girona Girona Spain
4. CIBER of Epidemiology and Public Health (CIBERESP) Madrid Spain
5. Keck School of Medicine University of Southern California Los Angeles CA USA