Funding for this research was provided by:
Received: 29 November 2016
Accepted: 14 March 2018
First Online: 10 April 2018
Ethics approval and consent to participate
: Ethical approval was not required for this secondary data analysis. Dr. Majid Ezzati provided his global dataset on anemia and vitamin A deficiency and approval to use these data. The other datasets used for this analysis are publicly available.
: Not applicable.
: The authors declare that they have no competing interests.
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