Funding for this research was provided by:
International Data Responsibility Group
Text and Data Mining valid from 2018-07-24
Received: 28 December 2017
Accepted: 10 July 2018
First Online: 24 July 2018
Ethics approval and consent to participate
: This study was under ethics review, oversight, and governance both in Greece and in the United States by the IOM Greek research ethics advisory board and the Institutional Review Board of the Harvard T. H. Chan School of Public Health (Protocol IRB16–2015), respectively. Oral informed consent was obtained from all participants.
: Not applicable.
: The authors declare that they have no competing interests.
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