et al., Int. J. Infect. Dis., July 1 2020, doi:10.1016/j.ijid.2020.06.099 (Peer Reviewed)
HCQ decreases mortality from 26.4% to 13.5% (HCQ) or 20.1% (HCQ+AZ). Propensity matched HCQ HR 0.487, p
=0.009. Michigan 2,541 patients retrospective. Before propensity matching the HCQ group average age is 5 years younger and the percentage of male patients is 4% higher which is likely to favor the treatment and the control respectively in the before-propensity matching results.
Some reported limtiations of this study are inaccurate . Corticosteroids were controlled for in the multivariate and propensity analyses as were age and comorbidities including cardiac disease and severity of illness. Age was an independent risk factor associated with mortality. HCQ was independently associated with decreased mortality, distinct from the steroid effect. 91% of all patients began treatment within two days of admission. HCQ was used throughout the study period, limiting time bias. Patients assigned to HCQ group had moderate and severe illness at presentation, which would favor worse outcome with HCQ.
Arshad et al., 7/1/2020, retrospective, USA, North America, peer-reviewed, 12 authors.
risk of death, 51.3% lower, RR 0.49, p = 0.009, treatment 162 of 1202 (13.5%), control 108 of 409 (26.4%).