et al., International Journal of Infectious Diseases, doi:10.1016/j.ijid.2020.12.041 (Peer Reviewed)
Retrospective database analysis with 17 existing users of HCQ and 5 severe cases, showing no significant difference for cases and higher risk for severe cases.
However, HCQ users are likely systemic autoimmune disease patients and authors do not adjust for the very different baseline risk for these patients. Other research shows that the risk of COVID-19 for systemic autoimmune disease patients is much higher overall, Ferri et al. show OR 4.42, p
Huh et al., 12/19/2020, retrospective, database analysis, South Korea, Asia, peer-reviewed, 8 authors.
risk of disease progression, 251.0% higher, RR 3.51, p = 0.11, treatment 5 of 8 (62.5%), control 873 of 2797 (31.2%), adjusted per study.
risk of COVID-19 case, 6.0% lower, RR 0.94, p = 0.82, treatment 17 of 122 (13.9%), control 7324 of 36600 (20.0%), adjusted per study.