Mehraet al[61] Multinational real-world analysis Teatment groups: n = 14,888Control group: n = 81,144 Mean daily dose: CQ 765 mg, (SD 308); HCQ 596 mg(126); CQ with a macrolide 790 mg(320); HCQ with a macrolide 597 mg(128).mean duration:CQ 6.6 days(2.4); HCQ 4.2 days(1.9);CQ with a macrolide 6.8 days(2.5); HCQ with a macrolide 4.3 days (2.0) A benefit of HCQ or CQ, when used alone or witha macrolide, on in-hospital outcomes for COVID-19 was not observed. Large multinational real-world data and large number of study populations. There may be potential confounders; It did not measure QT intervals and stratify the arrhythmia pattern; It did not determine whether the increased risk of death in-hospital and use of drug treatment regimens were directly related to cardiovascular risk; It did not observe the risk of the drug dose-response analysis.