Funding for this research was provided by:
Public Health Research Programme (11/3005/07)
Medical Research Council (MC_UU_12015/6, G106/1203, ES/G007462/1)
Wellcome Trust (087636/Z/08/Z)
British Heart Foundation (ES/G007462/1)
Economic and Social Research Council (ES/G007462/1)
National Institute for Health Research (ES/G007462/1)
UK Clinical Research Collaboration (MR/K023187/1)