1 Institute of Health Equity, Department for Epidemiology and Public Health, University College London, London WC1E 7HB, UK. Electronic address: m.marmot@ucl.ac.uk.
2 World Health Organization Regional Office for the Eastern Mediterranean, Nasr City, Cairo, Egypt.
3 Alliance for Health Policy and Systems Research, Geneva, Switzerland.
4 Institute of Health Equity, Department for Epidemiology and Public Health, University College London, London WC1E 7HB, UK.