1 Medical Research Council Integrative Epidemiology Unit (Lawn, Sallis, Wootton, Davey Smith, Davies, Hemani, Fraser, Munafò), School of Psychological Science (Lawn, Sallis, Wootton, Penton-Voak, Munafò), and Bristol Medical School (Sallis, Taylor, Davey Smith, Davies, Fraser), University of Bristol, Bristol, United Kingdom; National Institute for Health Research Biomedical Research Center, University Hospitals Bristol NHS Foundation Trust and University of Bristol, Bristol, United Kingdom (Taylor).