Study of SARS-CoV-2-IgG antibodies in 1122 health care workers in India finding 87% lower positives for adequate HCQ prophylaxis, 1.3% HCQ versus 12.3% for no HCQ prophylaxis.
Adequate prophylaxis is defined as 400mg 1/wk for >6 weeks.
Goenka et al., 10/24/2020, retrospective, India, South Asia, preprint, 11 authors.
risk of IgG positive, 87.2% lower, RR 0.13, p = 0.03, treatment 1 of 77 (1.3%), control 115 of 885 (13.0%), adjusted per study, odds ratio converted to relative risk.
Effect extraction follows pre-specified rules
prioritizing more serious outcomes. For an individual study the most serious
outcome may have a smaller number of events and lower statistical signficance,
however this provides the strongest evidence for the most serious outcomes
when combining the results of many trials.