- Correspondence to Professor Nir Eyal, Department of Global Health and Population, Harvard TH Chan School of Public Health, 651 Huntington Ave., FXB Building, Boston, MA 02115, USA;
- Received 1 February 2016
- Accepted 8 February 2016
- Published online 25 January 2017.
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.