- Correspondence to Dr G David Batty, Department of Epidemiology and Public Health, University College London, London, 1-19 Torrington Place, London, UK, WC1E 6BT.E.;
- Received 25 January 2016
- Revised 16 June 2016
- Accepted 3 July 2016
- Published online 12 August 2016.
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.