About the Authors

Nicholas A. Christakis

christakis@hcp.med.harvard.edu

Affiliations Faculty of Arts & Sciences, Harvard University, Boston, Massachusetts, United States of America, Health Care Policy Department, Harvard Medical School, Boston, Massachusetts, United States of America

James H. Fowler

Affiliations School of Medicine, University of California San Diego, La Jolla, California, United States of America, Division of Social Sciences, University of California San Diego, La Jolla, California, United States of America

Competing Interests

The authors have an equity stake in a company, MedNetworks, that is licensed by Harvard and UCSD to apply some of the ideas embodied in their work.

Author Contributions

Conceived and designed the experiments: NAC JHF. Performed the experiments: NAC JHF. Analyzed the data: NAC JHF. Wrote the paper: NAC JHF.