Small retrospective study with 63 patients (32 treated with HCQ), showing no effectiveness, however the baseline state of each arm significantly differs.
This preprint was submitted to NEJM but has not been published several months later.
Barbosa et al., 4/12/2020, retrospective, USA, North America, preprint, 5 authors.
risk of death, 147.0% higher, RR 2.47, p = 0.58, treatment 2 of 17 (11.8%), control 1 of 21 (4.8%).
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.