Received: 22 October 2018
Accepted: 31 January 2019
First Online: 13 February 2019
Ethics approval and consent to participate
: The study protocol was approved by the institutional review boards (IRB) at each respective study site (University of Southern California IRB for both Los Angeles County-University of Southern California Medical Center and Keck Hospital of University of Southern California; Quorum Review IRB for Huntington Hospital). As the study was non-interventional and there was no contact made with enrolled patients, the University of Southern California IRB and Quorum Review IRB allowed for informed consent to be waived. The study did not include vulnerable groups or where coercion of the patient could take place.
: Not applicable.
: The authors declare that they have no competing interests.
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