Funding for this research was provided by:
National Institute on Drug Abuse (UG3 DA0044830-02S1, 1UG1DA050067-01)
Center for Substance Abuse Treatment (1H79T1081387-01)
Received: 9 June 2020
Accepted: 13 October 2020
First Online: 21 October 2020
Ethics approval and consent to participate
: All procedures were approved by the University of Massachusetts Amherst Institutional Review Board. All participants received written information about the study during recruitment, including their right to withdraw from the study at any time, and they provided written informed consent.
: Not applicable.
: The authors report no competing interests.