Funding for this research was provided by:
National Institute on Drug Abuse (U01DA036221, U01DA036226, U01DA036233, U01DA036176, U01DA036225, U01DA036224, U01DA036158)
Received: 18 December 2019
Accepted: 22 April 2020
First Online: 13 May 2020
Ethics approval and consent to participate
: The study was conducted under the supervision of Chestnut Health Systems’ Institutional Review Board (IRB) for the protection of human subjects (IRB Research Study No. 1090–1213). Participation in the study was voluntary and participants could choose not to answer any question without consequences.
: Not applicable as no individual respondents identified.
: The authors declare that they have no competing interests.