Funding for this research was provided by:
National Institute on Drug Abuse (90056634)
Received: 19 March 2019
Accepted: 30 May 2019
First Online: 17 June 2019
Ethics approval and consent to participate
: Ethical issues of the ALIVE study have been continually approved by the Johns Hopkins Institutional Review Board. All participants in this study had provided written informed consent.
: All authors have read the manuscript and have consented this submission for publication.
: The authors declare that they have no competing interests.