Funding for this research was provided by:
U.S. Department of Veterans Affairs (CDA 07-022)
Received: 28 July 2017
Accepted: 1 May 2018
First Online: 8 May 2018
Ethics approval and consent to participate
: This study was approved by the Institutional Review Board at the University of Texas Health Science Center at San Antonio, the Research and Development Committee for the South Texas Veterans Health Care System and the Research Committee at University Health System. Written informed consent was received from participants prior to any research activity.
: The authors declare they have no competing interests.
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