Study		Exclusion reasons	Remarks	Reference(s)
HYDRA, 2020	randomized controlled trial		Initially found in Axfors et al. meta-analysis results published by Hernadez et al
CloroCOVID19, 2020	randomized controlled trial	inadequate or absent control group	This paper reports partial results from an unplanned interim analysis.Efficacy and safety criteria do not appear to have ever been assessed on the same number of patients (denominators are different for almost every criterion and are less than the number of patients randomized). Compared to the registration record, the patient eligibility criteria were changed.	Borba JAMA Netw Open 2020; 3:e208857 10.1001/jamanetworkopen.2020.8857 Mayla Borba for CloroCovid-19 Team medRxiv 2020.04.07.20056424
Ye et al., 2020	observational study	not relevant study design		Ye Eur Rev Med Pharmacol Sci 2020; 24:3390-3396 10.26355/eurrev_202003_20706
ChiCTR2000029975, 0	single-arm	not relevant study design
Duke university (Hydroxychloroquine), 2020	randomized controlled trial	cancelled by investigator
Duke University azithromycin, 2020	randomized controlled trial	cancelled by investigator	Discontinuated : Poor recruitment, strong evidence from larger trials of no therapeutic benefit
ChiCTR2000029826 (Cancelled by the investigator), 0	randomized controlled trial	cancelled by investigator
SIMPLE (Grein), 0	single-arm	no control group	single-arm with external control group	Grein N. Engl. J. Med. 2020; 382:2327-2336 10.1056/NEJMoa2007016
Erdem, 2020	retrospective cohort (registry)	no control group		Erdem HA Turk J Med Sci 2020 Nov 25. 10.3906/sag-2008-33
Hazan, 2021	case series	no control group		Hazan S et al. medrxiv;2021.07.06.21259924v1 10.1101/2021.07.06.21259924
Yamamura, 2020	single-arm	no control group		Yamamura H Crit Care 2020 Jul 9;24(1):413. 10.1186/s13054-020-03137-5
Hazan, 2021	case series	no control group		Hazan S et al. medrxiv;2021.07.06.21259924v1 10.1101/2021.07.06.21259924
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
Nasir, 2020	non randomized controlled trial	no clinically relevant endpoint		Nasir A et al. 10.2139/ssrn.3734478
Thakar, 2021	randomized controlled trial	no clinically relevant endpoint		Thakar A Indian J Med Res 2021 Jan 21. 10.4103/ijmr.IJMR_3665_20
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
IFORS (Pott-Junior), 2020	randomized controlled trial	other	The article has been retracted by Toxicology Reports	Pott-Junior H Toxicol Rep 2021;8:505-510. 10.1016/j.toxrep.2021.03.003
Elgazzar - treatment, 2020	randomized controlled trial	other	withdrawal of the publication	Elgazzar A et al. 10.21203/rs.3.rs-100956/v2
Barbosa, 2020	retrospective cohort	other	the only document variable for this study is a copy of a submission to NEJM. It is impossible to verify the veracity of this document. The paper was submitted apr 4th and since this date ther is no publication in NEJM or in other media (included preprint server).
Mallat, 2020	retrospective cohort	other	inapropriate statistical analysis. Time to events analyszed with means without taken into account the censure due to death or lost to follow-up	Jihad Mallat, Fadi Hamed, Maher Balkis, Mohamed A Mohamed, Mohamad Mooty, Asim Malik, Ahmad Nusair, Fernanda Bonilla medRxiv 2020.04.27.20082180 10.1101/2020.04.27.20082180
Mehra, 2020	retrospective cohort	other	the paper was retracted by 3 authors on June 4, 2020	Mehra MR Lancet 2020 May 22;S0140-6736(20)31180-6. 10.1016/S0140-6736(20)31180-6 Mehra MR Lancet 2020 Jun 13;395(10240):1820. 10.1016/S0140-6736(20)31324-6
Niaee (vs placebo), 2020	randomized controlled trial	other	On 8 October 2021 and 9 October 2021, two articles were published by subject-matter experts outlining concerns about various aspects of the study and, in particular, calling into question the randomization of participants. The authors and publishing journal have been alerted to these issues, and this note will be updated with any new information related to the publication.	Niaee MS et al. researchsquare 10.21203/rs.3.rs-109670/v1 Niaee MS et al. Asian Pacific Journal of Tropical Medicine 10.4103/1995-7645.318304
Mehra, 2020	retrospective cohort	other	the paper was retracted by 3 authors on June 4, 2020	Mehra MR Lancet 2020 May 22;S0140-6736(20)31180-6. 10.1016/S0140-6736(20)31180-6 Mehra MR Lancet 2020 Jun 13;395(10240):1820. 10.1016/S0140-6736(20)31324-6
Cadegiani -Iver, 2020	observational study	other	unappropriated control group	Cadegiani FA medrxiv https://doi.org/10.1101/2020.10.31.20223883