Funding for this research was provided by:
VHS Medical Center Research Grant (VHSMC 17035)
Article History
Received: 12 April 2018
Accepted: 12 July 2018
First Online: 25 July 2018
Ethics approval and consent to participate
: This study was approved by the Veterans Health Service Medical Center Institutional Review Board (2017–09–006-001), and informed consent was waived due to the retrospective nature of the study.
: Not applicable.
: The authors declare that they have no competing interests.
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