Received: 17 February 2021
Accepted: 9 March 2021
First Online: 20 March 2021
: The study was approved by The Ethical Boards of the included university hospitals in Belgrade, Serbia: (Reference number of Ethical Boards: CCS, no: 05/2016; ZvUMC, no: 05/2015; ZmUMC, no: 02/2015). Informed consent was obtained from all individual participants included in the study. All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards.
: Not applicable.
: The authors declare that they have no competing interests.