- Correspondence to Dr Luis de la Fuente, National Epidemiology Centre, Carlos III Health Institute C/Monforte de Lemos 5, Madrid 28029, Spain;
- Received June 4, 2013
- Revised October 16, 2013
- Accepted October 20, 2013
- First published November 14, 2013.
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.