Funding for this research was provided by:
North Carolina Department of Transportation (RP2018-83)
North Carolina Department of Health and Human Services (00035104)
Received: 28 June 2019
Accepted: 20 November 2019
First Online: 29 November 2019
Ethics approval and consent to participate
: This research did not use human subjects and therefore was exempt from University of North Carolina at Chapel Hill Institutional Review Board.
: Not applicable.
: The authors declare that they have no competing interests.