Funding for this research was provided by:
National Institute on Drug Abuse (R34-DA-036720-01, 1K01DA039336-01)
Received: 25 September 2017
Accepted: 16 January 2018
First Online: 25 January 2018
Ethics approval and consent to participate
: The study protocol was reviewed and approved by the University of Wisconsin – Madison’s Health Sciences Institutional Review Board, submission 2015-0280-CR002.
: Not applicable
: Authors Quanbeck and Johnson have a shareholder interest in CHESS Mobile Health, a public benefit corporation that develops healthcare technology for patients struggling with addiction. This relationship is managed by the authors and the University of Wisconsin – Madison’s Conflict of Interest Committee. The other authors declare that they have no competing interests.
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