Funding for this research was provided by:
Centers for Disease Control and Prevention (HHSD2002013M53959B)
Received: 23 August 2017
Accepted: 12 March 2018
First Online: 27 March 2018
Ethics approval and consent to participate
: RAND’s Institutional Review Board determined that this study did not involve human subjects.
: Not applicable.
: The authors declare that they have no competing interests.
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