Study		Exclusion reasons	Remarks	Reference(s)
Murohashi, 2020	prospective cohort	no control group		Murohashi K Respir Investig 2020 Aug 28;58(6):430-434. 10.1016/j.resinv.2020.08.001
Erdem, 2020	retrospective cohort (registry)	no control group		Erdem HA Turk J Med Sci 2020 Nov 25. 10.3906/sag-2008-33
Yamamura, 2020	single-arm	no control group		Yamamura H Crit Care 2020 Jul 9;24(1):413. 10.1186/s13054-020-03137-5
Dabbous, 2021	randomized controlled trial	other	Withdrawal of the publication.	Dabbous HM Arch Virol 2021 Jan 25;1-6. 10.1007/s00705-021-04956-9