About the Authors

Seung-Sup Kim

sskim@gwu.edu

Affiliation Department of Environmental and Occupational Health, The George Washington University School of Public Health and Health Services, Washington, D. C., United States of America

Yeonseung Chung

Affiliation Department of Mathematical Sciences, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea

Melissa J. Perry

Affiliation Department of Environmental and Occupational Health, The George Washington University School of Public Health and Health Services, Washington, D. C., United States of America

Ichiro Kawachi

Affiliation Department of Society, Human Development, and Health, Harvard School of Public Health, Boston, Massachusetts, United States of America

S. V. Subramanian

Affiliation Department of Society, Human Development, and Health, Harvard School of Public Health, Boston, Massachusetts, United States of America

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: SSK IK SVS. Analyzed the data: SSK YSC. Wrote the paper: SSK YSC MJP SVS.