- Correspondence to Dr Claire J Steves, Department of Twin Research & Genetic Epidemiology, King's College London, St Thomas’ Hospital Campus, 3rd & 4th Floor South Wing Block D, Westminster Bridge Road, London SE1 7EH, UK;
- Received October 6, 2015
- Revised November 9, 2015
- Accepted November 25, 2015
- First published December 30, 2015.
This web only file has been produced by the BMJ Publishing Group from an electronic file supplied by the author(s) and has not been edited for content.
- Data supplement 1 - Online supplement 1
- Data supplement 2 - Online supplement 2
- Data supplement 3 - Online supplement 3
- Data supplement 4 - Online supplement 4
- Data supplement 5 - Online supplement 5
- Data supplement 6 - Online supplement 6
- Data supplement 7 - Online supplement 7
- Data supplement 8 - Online supplement 8
- Data supplement 9 - Online supplement 9
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.