About the Authors

David A. Katz

dkatz7@u.washington.edu

Affiliation Department of Epidemiology, University of Washington, Seattle, Washington, United States of America

James N. Kiarie

Affiliation Department of Obstetrics/Gynaecology, University of Nairobi, Nairobi, Kenya

Grace C. John-Stewart

Affiliations Department of Epidemiology, University of Washington, Seattle, Washington, United States of America, Department of Medicine, University of Washington, Seattle, Washington, United States of America, Department of Global Health, University of Washington, Seattle, Washington, United States of America

Barbra A. Richardson

Affiliations Department of Biostatistics, University of Washington, Seattle, Washington, United States of America, Division of Public Health Sciences, Fred Hutchinson Cancer Research Cancer, Seattle, Washington, United States of America

Francis N. John

Affiliation Department of Obstetrics/Gynaecology, University of Nairobi, Nairobi, Kenya

Carey Farquhar

Affiliations Department of Epidemiology, University of Washington, Seattle, Washington, United States of America, Department of Medicine, University of Washington, Seattle, Washington, United States of America

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: JNK GJS BAR CF. Performed the experiments: JNK GJS BAR FNJ CF. Analyzed the data: DAK. Wrote the paper: DAK CF.