Received: 3 March 2020
Accepted: 18 June 2020
First Online: 1 July 2020
Ethics approval and consent to participate
: This article does not contain any studies with human participants or animals performed by any of the authors. This observational study was deemed exempt by the institutional review board that waived the need for consent because it used deidentified publicly available data.
: Not applicable.
: The authors declare that they have no competing interest.