Author Contributions: Dr West had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.
Study concept and design: West, Christian, Labrique, Rashid, Klemm, Katz, Akhter, Sommer.
Acquisition of data: West, Christian, Labrique, Rashid, Shamim, Klemm, Massie, Mehra, Schulze, Ali, Ullah, Akhter.
Analysis and interpretation of data: West, Christian, Labrique, Klemm, Massie, Mehra, Schulze, Wu, Katz, Banu, Akhter.
Drafting of the manuscript: West, Christian, Labrique, Klemm, Akhter.
Critical revision of the manuscript for important intellectual content: West, Christian, Labrique, Rashid, Shamim, Massie, Mehra, Schulze, Ali, Ullah, Wu, Katz, Banu, Sommer.
Statistical analysis: Christian, Labrique, Klemm, Massie, Wu, Katz.
Obtained funding: West, Sommer.
Administrative, technical, or material support: West, Labrique, Rashid, Shamim, Mehra, Schulze, Ullah, Akhter.
Study supervision: West, Christian, Labrique, Rashid, Shamim, Klemm, Mehra, Ali, Ullah.
Conflict of Interest Disclosures: All authors have completed and submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest and none were reported.
Funding/Support: The conduct of this trial was financially supported by Micronutrients for Health Cooperative Agreement HRN-A-00-97-00015-00 and Global Research Activity GHS-A-00-03-00019-00 between the Office of Health, Infectious Diseases and Nutrition, US Agency for International Development (USAID), Washington, DC, and Johns Hopkins University, Baltimore, Maryland, and Global Control of Micronutrient Deficiency grant 614 from the Bill and Melinda Gates Foundation, Seattle, Washington, with additional support from the USAID Mission, Dhaka, Bangladesh; the Ministry of Health and Family Welfare, Government of Bangladesh, Dhaka; the Micronutrient Initiative/Canadian International Development Agency, Ottawa, Ontario; the Nutrilite Health Institute, Access Business Group LLC, Buena Park, California; and the Sight and Life Research Institute, Baltimore, Maryland.
Role of Sponsors: None of the sponsors had any role in the design or conduct of the study; the collection, management, analysis, or interpretation of the data; or the preparation, review, or approval of the manuscript.
Additional Contributions: In addition to the authors, the study team comprised a field research organization of more than 800 Bangladeshi staff who carried out or supervised data collection, entry, and management and provided logistical, mapping, laboratory, and administrative support. Plasma retinol and β-carotene concentrations were measured at the Institute of Nutrition at Mahidol University (INMU), Salaya, Thailand, under the direction of Emorn Wasantwisut, PhD, and Pongtorn Sungpuag, DSc, for whom compensation was provided through a memorandum of understanding between the Center for Human Nutrition at Johns Hopkins Bloomberg School of Public Health and INMU.