Received: 2 October 2016
Accepted: 14 December 2017
First Online: 12 January 2018
Ethics approval and consent to participate
: Ethics approval to conduct this study was provided by the Emory University Institutional Review Board. Informed consent to participate in this study was obtained from each participant prior to study enrollment. The study was registered atExternalRef removed, identifier NCT01556282, on March 16, 2012.
: This manuscript contains only aggregate results and does not present any individual person’s data. This manuscript does not contain details, images, or videos relating to any individual person and therefore does not require written informed consent from each individual for publication.
: The authors declare that they have no competing interests.
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