1. From the Institute of Cardiovascular Medicine and Sciences, Liverpool Heart and Chest Hospital, Liverpool, UK (N.M.H.); Health Care Evaluation Group, Department of Epidemiology and Public Health, University College London, London, UK (S.S., M.B., R.R.); Pensions and Annuity Group, Legal and General plc, UK (H.L.); and Division of Public Health and Policy, University of Liverpool, Liverpool, UK (M.O.F., S.C.).