Funding for this research was provided by:
William U Gardner Memorial Student Research Fellowship
Received: 8 February 2018
Accepted: 29 May 2018
First Online: 20 June 2018
Ethics approval and consent to participate
: Our study is exempt from review by the Yale Human Research Protection Program because it uses a pre-existing, de-identified public database.
: Not applicable.
: The authors declare that they have no competing interests.
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