- Correspondence to Justin M Feldman, Department of Social and Behavioral Sciences, Harvard T.H. Chan School of Public Health, 677 Huntington Avenue, Boston, MA 02115, USA;
- Received March 6, 2015
- Revised June 8, 2015
- Accepted June 17, 2015
- First published July 1, 2015.
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.