Rosenberg et al[60] Retrospective multicenter cohort study HCQ group:n = 271;HCQ ＋azithromycin group:n = 735control group:n = 221 HCQ:200 mg/400 mg/600 mg/other/unknown, frequency: once a day/twice a day/other/unknownazithromycin:200 mg/250 mg/400 mg/500 mg/other/unknown, methods:Oral/IV/unknown,frequency: only once/once a day/twice a day/other/unknown Treatment with HCQ, azithromycin, or both, compared with neither treatment, was not significantly associated with differences in in-hospital mortality.