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by AnthonBerg 996 days ago
The un-cited Cochrane review in question does not say that.

From Cochrane.org:

Statement on 'Physical interventions to interrupt or reduce ... - Cochrane

Mar 10, 2023

Many commentators have claimed that a recently-updated Cochrane Review shows that 'masks don't work', which is an inaccurate and misleading interpretation. It would be accurate to say that the review examined whether interventions to promote mask wearing help to slow the spread of respiratory viruses, and that the results were inconclusive.

Repeating the important part:

the review examined whether interventions to promote mask wearing help to slow the spread of respiratory viruses

Conversely, here’s a good study that shows that consistent use of FFP3 respirator masks drastically reduced transmission among workers on a hospital ward: https://elifesciences.org/articles/71131

Note that the study only had the workers wearing FFP3 masks on shifts, and community transmission was high at the time. Therefore the study “leaked” and good masks work better than the numbers in the study might seem to indicate. Face-fitting masks do work, and very well. Of course they do. It’s all very clear if you dig into the aerosol physics.

2 comments

It looks like FFP3 are analogous to N99 masks.

A mask mandate that permits "wrap a piece of T-shirt over your mouth, some of the time, sometimes even covering your nose" (which is not far from what I saw for much of 2020) is, unsurprisingly, going to be more effective at ensuring grudging compliance with a mandate than it is to reduce the spread of an airborne virus.

This is the problem with mask absolutists. They take data from masks that are super effective (hospital setting, correct usage, basically gluing the mask to your face) and extrapolate it to some guy on the subway with a cloth mask. It’s a bad way to make public policy, and I don’t really understand the motivation behind it.
I am not a mask absolutist.

Close family is at risk of severe illness or death from COVID. We provide for a small child. We do not have much margin.

I’d like to ask you to imagine the social repercussions of masking. It’s hard. I do not want to be weird. I do not want to be an outcast, practically speaking. I don’t want to wear a mask.

I just don’t have any margin in the other direction.

Also:

What is it about a hospital setting that makes a given type of mask more effective?

Answer: Nothing.

Hospitals are places where it’s easier to run a trial, and where it’s harder to avoid infection.

Face-fitting masks do not require glue. Fitting a mask isn’t that hard.

Cloth masks don’t work and never did.

The objective is to not die or be maimed by a virulent pathogen, or rather: to have the option. Clarity on effective means for those who want it. I want effective means because I need them. The objective is not social classification of mask wearers or categorization of discussion types or labeling people as cartoons.

The objective is clear information as input into serious personal decision-making. The guy on the subway is not in scope.

I think hospital workers experience with wearing masks (and the resulting "they have chosen a mask size and from experience have adjusted the mask to make it comfortable and effective") and the ability for the hospital to prohibit facial hair in their workers that's incompatible with effective mask use are key differences between hospital staff and Joe/Jane Public on the streets.

In terms of being weird: there are enough people wearing masks and most people literally care more about what they're going to have for dinner than whether or not you're wearing a mask. If a mask helps your family, don't worry about the epsilon weird aspect (as I'm sure you have already calculated).

Well said. Thank you.

I think I can also pretty decisively say that hospital purchasing optimizations give face-fitting masks a bad rap. The FFP2 masks that hospital staff wear here are cheap and very uncomfortable. This bleeds into society as a negative view.

There’s also another aspect: The difference between a N95/FFP2/whatever mask as part of the industrial production of a verifiable sanitization chain in a hospital on one hand, and on the other as a piece of fabric that’s ludicrously effective at stripping infectious particles from the air.

There are many more edge cases in a hospital, and many more pathogens. In private life – mine at least – it’s only really COVID that matters. In that case a mask can be reused again and again and it’s OK to touch it, basically.

Re. being weird:

I don’t mind.

The weirdness hurts the family. There’s a big, big gap of dissonance between what we need to do and what public health authorities say. This includes flat out demonstrably wrong statements about transmission where I live. This dissonance makes the family weird, and it has caused severe social isolation of a mother with a young child.

I want to assure the reader that we don’t ask for much. We are very, very polite. We don’t demand anything, we are not difficult.

It’s purely the astounding dissonance. People don’t know what to do and just fade away.

It’s a very painful way to be weird. You feel it in your bones and your soul how unnatural it is.

Occam's razor here is that your interest in masks is a mental illness, and not because someone in your family is so immunocompromised or whatever that the mask is standing between that person and certain death. Is it possible that the latter is the case? Maybe. But in my view almost all cases of people stubbornly wearing masks are just psychiatric in nature.

I know my comment will just make you angry, because "you're different". But, maybe someone else will see it and consider their psychological state on this topic.

Precisely.
I would encourage readers to read the “Main results” section of the review for themselves. It takes under 5 minutes. Don’t trust a commenter on any online forum on this topic (myself included), as it’s completely politicized.
Also read the studies themselves.

And the criticism of the Cochrane-method review.

And the studies not cited.

As well as the studies on the mechanics of transmission.

I think people can rely on the authors to put the main results in the "Main results" section. What they can't rely on is potential nutters in Internet forums.