Article History
Received: 16 January 2018
Accepted: 24 May 2018
First Online: 30 May 2018
Ethics approval and consent to participate
: This study was deemed exempt from ethics review by the Harvard T.H. Chan School of Public Health Institutional Review Board, as the MICS data used are publicly available and fully de-identified.
: The authors declare that they have no competing interests.
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