1. Bristol Medical School, Population Health Sciences University of Bristol Bristol UK
2. Medical Research Council Integrative Epidemiology Unit University of Bristol Bristol UK
3. K.G. Jebsen Center for Genetic Epidemiology, Department of Public Health and Nursing, NTNU Norwegian University of Science and Technology Norway
4. National Institute for Health Research, Bristol Biomedical Research Centre University Hospitals Bristol NHS Foundation Trust and University of Bristol Bristol UK
5. Addiction and Mental Health Group (AIM), Department of Psychology University of Bath Bath UK
6. Department of Non‐communicable Disease Epidemiology, Faculty of Epidemiology and Population Health LSHTM London UK