Received: 22 February 2021
Accepted: 31 May 2021
First Online: 9 June 2021
: Ethics approval was obtained from the University of the Free State’s Health Sciences Research Ethics Committee (HSREC), with reference number UFS-HSD2020/1544/2411. Informed consent was not taken from each individual, as this was a retrospective study.
: Not applicable (retrospective study)
: The authors declare that there is no competing interest.