Text and Data Mining valid from 2019-02-14
Received: 26 November 2018
Accepted: 1 February 2019
First Online: 14 February 2019
Ethics approval and consent to participate
: All data was accessed as part of ongoing public health surveillance activities and was therefore considered exempt from consent to participate by the Veterans Health Administration Office of Research Oversight which considers public health investigations as operational activities and not research in the Veterans Health Administration. Permission to access data was granted through the Veterans Health Administration Director of National Data Systems, Austin Information Technology Center, 1615 Woodward Street, Austin, Texas 78,772, in accordance with the Privacy Act of 1974; System of Records entitled, “National Patient Databases – VA” (121VA10A7).
: Not applicable.
: The authors declare that they have no competing interests.
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