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EYE ON THE NEWS
Do Masks Work?
A review of the evidence
Jeffrey H. Anderson
August 11, 2021 Covid-19Health CarePolitics and law
Do Masks Work? ...... A review of the evidence
Since we are constantly told that the CDC and other public-health entities are basing their recommendations on science, it’s crucial to know what, specifically, has been found in various medical studies. Significant choices about how our republic should function cannot be made on the basis of science alone—they require judgment and the weighing of countless considerations—but they must be informed by knowledge of it.
In truth, the CDC’s, U.K.’s, and WHO’s earlier guidance was much more consistent with the best medical research on masks’ effectiveness in preventing the spread of viruses. That research suggests that Americans’ many months of mask-wearing has likely provided little to no health benefit and might even have been counterproductive in preventing the spread of the novel coronavirus.
It’s striking how much the CDC, in marshalling evidence to justify its revised mask guidance, studiously avoids mentioning randomized controlled trials. RCTs are uniformly regarded as the gold standard in medical research, yet the CDC basically ignores them apart from disparaging certain ones that particularly contradict the agency’s position. In a “
Science Brief” highlighting studies that “demonstrate that mask wearing reduces new infections” and serving as the main public justification for its mask guidance, the CDC provides a helpful matrix of 15 studies—none RCTs. The CDC instead focuses strictly on observational studies completed after Covid-19 began. In general, observational studies are not only of lower quality than RCTs but also are more likely to be politicized, as they can inject the researcher’s judgment more prominently into the inquiry and lend themselves, far more than RCTs, to finding what one wants to find.
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