1. From the LSE Health, Department of Social Policy, London School of Economics and Political Science, London, United Kingdom (H.N.); Drug Policy Research Group, Department of Population Medicine, Harvard Medical School and Harvard Pilgrim Health Care Institute, Boston, MA (H.N.); Department of Epidemiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands (G.v.V.); School of Social and Community Medicine (J.P.T.H.) and School of Social and Community Medicine (A...