The study though, crucially, is a preliminary one, which means it has not undergone a rigorous peer-review process. It’s also an observational study, which means we’re not comparing the same treatments given to one group to another receiving a placebo. The gold standard for such studies is a randomized, double-blind study in which neither the patients nor doctors know who is getting the treatment vs. the placebo. That’s really the crucial point. The 2.9 times higher survival rate is not compared to those who didn’t receive the treatment; it’s compared to those who received less of the treatment. And as critics of the study have noted, there are other very valid reasons those who received less of the treatment might have had worse outcomes, including the severity of their cases. “It’s likely that patients who died rapidly received less total (of the two drugs) because they were dead; one can’t conclude from these data that they died because they got fewer doses,” Neil Schluger, chairman of New York Medical College’s Department of Medicine, told PolitiFact. “It’s also likely that, if they received lower doses on a daily basis, it’s because they were sicker to begin with.”