- Correspondence to Dr Christopher G Owen, Division of Population Health Sciences and Education, St George's, University of London, Cranmer Terrace, London SW17 0RE, UK;
- Accepted December 28, 2011
- First published February 13, 2012.
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.
Files in this Data Supplement:
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.