Funding for this research was provided by:
John D. and Catherine T. MacArthur Foundation (15-107912-000- INP)
Received: 29 November 2017
Accepted: 12 February 2018
First Online: 5 March 2018
Ethics approval and consent to participate
: This study was granted IRB approval by the Harvard T.H. Chan School of Public Health Office of Human Research Administration.
: Not applicable.
: The authors declare they have no competing interests.
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