Received: 13 October 2020
Accepted: 1 April 2021
First Online: 27 May 2021
: This study was exempted by a local Medical Research Ethics Committee after being assessed as not subject to the Medical Research Involving Human Subjects Act due to the use of retrospective data.
: Not applicable.
: C.S. Palmer contributes to the AIS Content Subcommittee of the AAAM.