One of these "studies" is a 2-page Google Doc with no real data. Another is the discredited Raoult study, which is under investigation by the journal . Another study cited is also by Raoult's team. The Brazil study (ref. 29) doesn't seem to have passed peer review (yet?) and has severe methodological flaws. Like the Raoult studies, the Brazil study was not randomized, but makes no attempt to control for confounding by indication or self-selection, such as with propensity score matching or similar methods commonly used in observational studies. The last study cited isn't a study, but an article from a local news station.