About the Authors
- Debbie A Lawlor, Abigail Fraser, George Davey Smith
- Department of Social Medicine, University of Bristol, Bristol, United Kingdom
- Shah Ebrahim
- Department of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, United Kingdom
The authors have declared that no competing interests exist.
DAL, SE, and GDS designed the study. DAL analyzed the data and enrolled patients. All authors contributed to writing the paper. AF made a substantial contribution to interpreting results.