Funding for this research was provided by:
Centers for Disease Control and Prevention (U01 GH0000029, U5 19 GH000636)
Text and Data Mining valid from 2019-03-08
Received: 24 July 2018
Accepted: 28 February 2019
First Online: 8 March 2019
Ethics approval and consent to participate
: The Institutional Review Boards (IRBs) and ethics committees of the participating institutions, the Chinese Center for Disease Control and Prevention (China CDC; protocol 201,110), United States (US) Centers for Disease Control and Prevention (CDC, protocol 6140), and the US National Cancer Institute (NCI, protocol 11CN165), approved the project before data collection began and have since obtained renewed IRB approval annually. Prior to data collection, all mothers, and children aged 18 years and over, signed written consent to participate in the study. Children aged under 18 years provided signed Assent, and their parents provided written consent for them to participate in the study.
: Not applicable.
: The authors declare that they have no competing interests.
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