Text and Data Mining valid from 2019-01-03
Received: 14 September 2018
Accepted: 10 December 2018
First Online: 3 January 2019
Compliance with ethical standards
: All authors certify that they do not have any conflict of interest.
: The study was approved by the Institutional Review Board (IRB) of University of Virginia (UVA).
: This is a retrospective study and informed consent was not required.