Funding for this research was provided by:
National Institutes of Health (HD052104, HD052102)
Received: 20 December 2017
Accepted: 15 May 2018
First Online: 31 May 2018
Ethics approval and consent to participate
: Institutional review boards (IRB) at clinical sites and the Harvard T.H. Chan School of Public Health approved the study. Parents or legal guardians provided written informed consent for their children’s participation. Youth consented or assented per local IRB guidelines.
: The authors declare that they have no competing interests.
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