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Filtering Evidence

"J.A. Schumpeter said that the first thing a man will do for his ideals is lie. It is not necessary to lie, however, in order to deceive, when filtering will accomplish the same purpose."

- Thomas Sowell. Intellectuals and Society (p. 128). Basic Books. Kindle Edition.

Rhetoric, cherry picking, and lying by omission: we use different terms depending on the context and our perception of intent. Very often, however, people perform information filtering even on themselves without conscious awareness, paying more attention to evidence that supports their a priori views and discounting or ignoring conflicting evidence. We call this Confirmation Bias.

Though the scientific method was designed to mitigate as much of this human tendency as possible, doctors and scientists are just as prone to this failing as everyone else, even absent conflicts of interest from politics and funding.

The CDC's publications regarding facemasks are a prime example of what this looks like in practice, coming from an organization which purports to be objective. To start, I have read all 69 studies cited by the CDC in their “Science of Masking to Control COVID-19” and “Science Brief: Community Use of Cloth Masks to Control the Spread of SARS-CoV-2”. Over 75% of the CDC’s supporting citations in these documents are opinion, laboratory studies, or even evidence against the efficacy of masks, with the rest being weak observational studies (e.g. “Intervention with Trend Analysis”). The CDC does not adduce a single randomized controlled trial in which the results definitively support facemask efficacy to control the spread of respiratory viral infections, and they ignore more than 18 randomized controlled trials which provide evidence that facemasks are not effective which is far stronger than anything they cite.

I have done a thorough survey of the medical literature from the last 100 years, and to date there are at least 85 published studies providing directly-relevant evidence that facemasks do not inhibit the spread of respiratory viral infections. This is in addition to more than 80 other published studies providing substantial background evidence that discourages facemask use.

The snapshot results of my research are available to view and download here as poster-sized pdfs. The studies cited will be either linked or hosted on my resources and downloads page.

If mechanistic laboratory studies, intuition, and theory suggest that masking should work, but real-world observations fail to bear this out, then there is something wrong with the initial hypothesis, the cited laboratory studies are not capturing all the major factors relevant to mask use, and mandatory masking is wrong even on a utilitarian ethic.

I don't claim to be immune to confirmation bias either, but that's part of the point - no one is. The question is, which side in this debate is attempting to usurp your decisions, coerce your compliance, and which side is giving you the broadest information and supporting your right to make up your mind for yourself and act accordingly?

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