About the Authors

Vladimir Canudas-Romo

vcanudas@health.sdu.dk

Current address: Max-Planck Odense Center on the Biodemography of Aging. J.B., Winslφws Vej 9, 5000 Odense C, Denmark

Affiliations Max Planck Odense Center, University of Southern Denmark, Denmark, Department of Population, Family and Reproductive Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America

Li Liu

Affiliation Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America

Linnea Zimmerman

Affiliation Department of Population, Family and Reproductive Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America

Saifuddin Ahmed

Affiliation Department of Population, Family and Reproductive Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America

Amy Tsui

Affiliation Department of Population, Family and Reproductive Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: VCR AT SA. Performed the experiments: VCR LL LZ. Analyzed the data: VCR LL LZ. Contributed reagents/materials/analysis tools: VCR LL LZ. Wrote the paper: VCR LL LZ SA AT.