Article History
Received: 4 January 2018
Accepted: 27 April 2018
First Online: 3 May 2018
Ethics approval and consent to participate
: This study was approved by the Institutional Review Board (IRB) of University of Texas Health Science Center at Houston (HSC-DB-17-0370). The need for consent was waived by the IRB, since the study was a retrospective chart review type of study.
: The authors declare that they have no competing interests.
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