1. University of East Anglia; Norwich Medical School; Norwich Research Park Norwich Norfolk UK NR4 7TJ
2. London School of Hygiene & Tropical Medicine; Department of Non-communicable Disease Epidemiology; Keppel Street London UK WC1E 7HT
3. University of Bristol; MRC Integrative Epidemiology Unit, School of Social and Community Medicine; Oakfield House Oakfield Grove, Clifton Bristol UK BS8 2BN