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"The Cochrane review, for all of its controversy, is a reminder that more research on masking is needed, if only to address whether pro-mask policies warrant the rage they incite. You would think that the policy makers who encouraged masking would have made finding that support a priority."

Well, it depends on what the intent of the masking policy is. Unlike, say, a vaccine or an antiviral, where there are several possibilities and you have good reason to believe that if you test enough of them, at least one will work, and you want to know which one, masking was to a certain extent a placebo whose main purpose was to provide psychological support. I mean, if even in controlled studies N95 masks block "57 to 90 percent of particles", it's a bit tricky to see how that will block a self-replicating virus that doesn't need to hit you with enough particles to take you down, it just needs to get a small number (in theory, one) particle snuck past your immune system.

But what masks, and masking policy, did do was keep 50+% of the population from running screaming into the wilderness and hiding until they starved. They probably were the only mental health precaution that did any mitigation of the many other mental-health-damaging policies. If you did a well-controlled study that showed that you needed full SCBA to actually block a respiratory virus, it would have removed the only emotional prop that a lot of people had.

“if even in controlled studies N95 masks block ’57 to 90 of particles’”

source? what kind of fake news is this??? they are called N95 for a reason. They filter AT LEAST 95% of the particles above a certain size. You can argue that many people wear them wrong which reduces their effectiveness…that i agree with.

I'm no expert, don't know the details on masks or particles or coronaviruses or covid-19, but you did add an "above a certain size" qualifier, which hypothetically leaves room for both statements, yours and the previous, to be true.

and, to that point, the previous comment included an assertion, not in exactly so many words, that suggests that the N100 - N95 = N5% of particles could be plenty to readily transmit the infection

and, for an N95 mask to operate at N95 it needs to be carefully "fitted" to the face, perhaps meaning that the practical effectiveness among the general public might be below 95%

and we are in a discussion here of a published paper that says "masks didn't do anything" so shooting down what the GP comment said isn't really a priority.

Although what the GP comment said about masks being a psychological placebo seems to be a pure fantasy given that the comment is made in the context of talking about how much divisiveness the masks provoked (though whether they did or not isn't necessarily important, whether they work or not is.)

> and we are in a discussion here of a published paper that says "masks didn't do anything"

After reading Cochrane's own list of caveats about their study that feels like overstating it.

Also for your specific phrasing, "masks didn't do anything", what part of the studies they looked at do you think looked at COVID mask guidance?

Only a tiny part of the studies they looked at were even in the context of COVID: Two out of 78. Funnily enough, these two papers claim that masks were effective. (Why only include two COVID-times studies in this update, out of the dozens that have been published?)

I said a lot more interesting things than the wording of one phrase you are picking on. I read your take as "eager to defend the mainstream squarequote-science" on this topic.

we know they lied about what they knew about the origins of covid-19 and gain of function research, the very same people were in charge of mitigating/vaccinating/curing covid, we know they had conflicts of interest, we know they suppressed open airing of dissent, so I don't trust what the experts are writing down at all, and I don't waste a lot of time reading about the subject.

My comment you replied to I think stands as a reasonable explanation of what I was responding to, but really must be read in the context of that comment (like quote him then quote me) and not standing alone.

That's a direct quote from the article we're talking about here? It has a link.
"They filter AT LEAST 95% of the particles above a certain size."

That's a common misunderstanding; they filter at least 95% of particles of all sizes. It's actually intermediate-sized particles (around 0.1 - 1 micron) that're hardest to capture. Smaller particles are more subject to Brownian motion, which makes them jiggle around more, and hence makes them more likely to bump into one of the respirator's strands... where they'll stick, thanks to Van der Waals forces.

N95 masks (if properly fitted) block at least 95% of particles in that 0.1 - 1 micron range (they're tested with particles around 0.3 microns), and even higher percentages of particles that're either larger or smaller than that.

Reference: https://blogs.cdc.gov/niosh-science-blog/2009/10/14/n95/ (especially figure 2)

FTA:

> Masking has widely been seen as one of the best COVID precautions that people can take. Still, it has sparked ceaseless arguments: over mandates, what types of masks we should wear, and even how to wear them. A new review and meta-analysis[0] of masking studies suggests that the detractors may have a point. The paper—a rigorous assessment of 78 studies—was published by Cochrane, an independent policy institution that has become well known for its reviews. The review’s authors found “little to no” evidence that masking at the population level reduced COVID infections, concluding that there is “uncertainty about the effects of face masks.” That result held when the researchers compared surgical masks with N95 masks, and when they compared surgical masks with nothing.

[0] https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD...