About the Authors

Sarah J. Lewis

S.J.Lewis@bristol.ac.uk

Affiliation School of Social and Community Medicine, University of Bristol, Bristol, United Kingdom

Ali Murad

Affiliation School of Social and Community Medicine, University of Bristol, Bristol, United Kingdom

Lina Chen

Affiliation School of Social and Community Medicine, University of Bristol, Bristol, United Kingdom

George Davey Smith

Affiliations School of Social and Community Medicine, University of Bristol, Bristol, United Kingdom, MRC Centre for Causal Analysis in Translational Epidemiology, School of Social and Community Medicine, University of Bristol, Bristol, United Kingdom

Jenny Donovan

Affiliation School of Social and Community Medicine, University of Bristol, Bristol, United Kingdom

Tom Palmer

Affiliations School of Social and Community Medicine, University of Bristol, Bristol, United Kingdom, MRC Centre for Causal Analysis in Translational Epidemiology, School of Social and Community Medicine, University of Bristol, Bristol, United Kingdom

Freddie Hamdy

Affiliation Nuffield Department of Surgery, John Radcliffe Hospital, Oxford, United Kingdom

David Neal

Affiliation Department of Oncology, University of Cambridge, Addenbrooke's Hospital, Cambridge, United Kingdom

J. Athene Lane

Affiliation School of Social and Community Medicine, University of Bristol, Bristol, United Kingdom

Michael Davis

Affiliation School of Social and Community Medicine, University of Bristol, Bristol, United Kingdom

Angela Cox

Affiliation Institute for Cancer Studies, School of Medicine and Biomedical Sciences, University of Sheffield, Sheffield, United Kingdom

Richard M. Martin

Affiliations School of Social and Community Medicine, University of Bristol, Bristol, United Kingdom, MRC Centre for Causal Analysis in Translational Epidemiology, School of Social and Community Medicine, University of Bristol, Bristol, United Kingdom

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Planned and conducted the analysis and wrote the paper: SJL. Contributed to the analysis and to writing the paper: AM LC. Conceived the idea for the paper and advised on the analysis: GDS. Conceived and managed the RCT and the nested-case control study: JD. Carried-out the IV analysis and contributed to writing the paper: TP. Conceived and managed the RCT: FH DN. Managed the day-to-day running of the RCT: JAL. Managed the data for the nested case-control study: MD. Co-ordinated the lab work for this study: AC. Supervised the analysis and contributed to writing the paper: RMM.