8 ms·

> You will find literally zero papers credibly claiming otherwise. Of the papers cited in the WHO meta-analysis of face masks and infection [1], all of the (th

by timr 5y ago

> You will find literally zero papers credibly claiming otherwise. Of the papers cited in the WHO meta-analysis of face masks and infection [1], all of the (three!) papers from a non-health-care setting had a confidence interval overlapping 1.0 (i.e. "no benefit"). Of those in a health-care setting, about half had confidence intervals overlapping 1.0 (i.e. "no benefit"): https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(20)31142-9/fulltext#seccestitle140 https://www.thelancet.com/journals/lancet/article/PIIS0140-6... The literature in this area was exceptionally ambiguous prior to 2020, and hasn't improved over the course of the pandemic. You've just made a provably incorrect claim. If you did it on YouTube, I guess you'd be banned! (just kidding; we all know that you can't possibly misinform people when you're agreeing with the party line!) [1] https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(20)31142-9/fulltext#seccestitle140 https://www.thelancet.com/journals/lancet/article/PIIS0140-6...

nickthemagicman 5y ago
Thanks for posting. No one on the pro-mask side reads scientific papers. They're fascists and want to crush their opposition through controlling the narrative instead of actual science.
kgarten 5y ago
Anecdotal, how do you explain the non existing flue season (last autumn ) and the low incidences in Japan? We got higher rates during the Olympic. I live in Tokyo, Japan and visit US/Europe often. The only significant difference I see is the willingness to wear masks. And there's way less space here (packed subways etc.)
- timr 5y ago
  Well, any rational conversation about Japan has to start with the observation that cases are at an all-time high right now: https://www.asahi.com/topics/word/%E3%82%B3%E3%83%AD%E3%83%8A%E3%82%A6%E3%82%A4%E3%83%AB%E3%82%B9.html?iref=evb_1 https://www.asahi.com/topics/word/%E3%82%B3%E3%83%AD%E3%83%8... I don't think changing rates of masking can explain that change. > Anecdotal, how do you explain the non existing flue season (last autumn ) and the low incidences in Japan? We got higher rates during the Olympic. I haven't seen any data on flu during the olympics, so I can't comment on that. Covid cases, of course, were shooting up long before the first athletes even arrived in Japan (see above). To answer your question, nobody knows why flu "disappeared" during the last year. My hypothesis is a combination of two things: 1) it didn't disappear, it just spread less due to to the dramatic reduction in international travel (plus maybe closure of schools). 2) we stopped testing for flu at rates necessary to detect it. Our prior surveillance system for influenza was pretty limited, and most of it switched to Covid in 2020. In general, I think people fixate on masks far too much, because they're visible. Even in Japan, what qualifies as a mask would make Americans in the "mask compliant" cities laugh out loud. I routinely see people wearing these on Instagram and on television: https://www.superdelivery.com/product_image/812/8/8128738_1000.jpg https://www.superdelivery.com/product_image/812/8/8128738_10...
  - kgarten 5y ago
    anything that interfere with droplet dispersion is better than nothing ... no? https://www.youtube.com/watch?v=pwOwMsCc6NA https://www.youtube.com/watch?v=pwOwMsCc6NA https://www.youtube.com/watch?v=GAvO_QdO9eM https://www.youtube.com/watch?v=GAvO_QdO9eM Seems basic to me ... If the droplets from me don't reach to the first person in the cinema I cannot infect them.
    - belorn 5y ago
      > If the droplets from me don't reach to the first person in the cinema I cannot infect them. It would be nice if that was true. In a small study here in Sweden they tested for covid particles in the AC system, and found particles in every single place they tested. This in a major hospital where everyone are wearing masks, and where the AC is located in the ceiling. The finding was not what the researcher was expecting, especially not in the AC system located on the roof. How much interference a mask has is determined by the leak rating, but for most surgical masks there are no protection for the finer droplets in coughs and sneezes. In a similar style, people though initially that bath houses and saunas would be safe against covid because the large droplets in the humid air would drop quickly to the ground. Later it was generally agreed here that the conclusion was incorrect and all public bath houses and saunas closed. Like with masks, humid air might be better than nothing but you really do not want to be near a person who are sick unless you got yourself an air filter and face shield.
      - kgarten 5y ago
        Yes, that's the point masks are better than nothing. They might reduce the likelihood (without much of a negative impact). That's why we should wear them. A vaccination also just reduces the likelihood you get covid. People can still get it and still spread it, even if they are vaccinated. It just reduces the likelihood and masks might do that as well ...
        belorn 5y ago
        Yes, through masks don't reduce the likelihood of infection in the same way like vaccinations. The vaccination significant reduce infection rate for the person who takes it. Any secondary effect on other people is the result of the vaccinated person not being sick. Mask on other hand might in a limited way reduce spread if the person who wear it is sick. Masks without intake filters has zero effect on the person who wears the mask. Vaccinations also have requirements with generally 90%+ protection, while masks has anything from 0 to 90% effectiveness in filtering breath emissions. As a effective measure against covid, vaccinations are a much more effective and powerful tool. After two years and in my experience, you can't have large gatherings and expect a low risks. Neither vaccines nor mask nor the combination of both can produce enough of an defense. 2m distancing, washing hands, and keeping human gatherings inside to an absolute minimum is the only way, and then follow up with mass vaccinations. I don't think given current scientific knowledge that one can cheat that process.
srinivgp 5y ago
The paper you linked to says, in its summary section, "For the general public, evidence shows that physical distancing of more than 1 m is highly effective and that face masks are associated with protection, even in non-health-care settings, with either disposable surgical masks or reusable 12–16-layer cotton ones, although much of this evidence was on mask use within households and among contacts of cases." But I assume you mean that the meta analysis didn't claim masks were useless, those three underlying papers did? I'm not sure what those three were, though, maybe I missed it. I found all the papers used but there were like a dozen in the non-health-care setting.
- timr 5y ago
  That is their interpretation of the meta-analysis, yes ("summary section" == "discussion section"). That is not a statement of fact, but of the authors' opinions about the facts reported. The data stands on its own -- though in this case, since it's a meta-analysis with fancypants statistical re-weighting of the data, the line between "data" and "analysis" is decidedly blurred. > But I assume you mean that the meta analysis didn't claim masks were useless, those three underlying papers did? I'm not sure what those three were, though, maybe I missed it. I found all the papers used but there were like a dozen in the non-health-care setting. The data they have presented, aggregating ~all of the prior research literature on masks, shows a weak effect, at best. Only by mixing data from different settings (mostly hospitals) and different types of masks (from cloth to respirators) and re-weighting the conclusions do they arrive at this claim of even weak effectiveness. Do masks work? Based on the literature, the only honest answer is "maybe they have a small effect, but the evidence isn't very good." Compare this to what you see repeated in the media and by "experts". The truth is...most of these people haven't read the papers, and are just repeating what they've heard.
kgarten 5y ago
Not improved?? I just checked nature... https://www.nature.com/articles/s41591-020-0843-2 https://www.nature.com/articles/s41591-020-0843-2 https://www.nature.com/articles/d41586-020-02801-8 https://www.nature.com/articles/d41586-020-02801-8 https://www.nature.com/articles/s41467-021-24115-7 https://www.nature.com/articles/s41467-021-24115-7 Seems pretty clear to me.
- timr 5y ago
  The Leung et. al. paper (first link) should never have passed editorial review. Look at figure 1: the only significant result in the entire paper (1a, panel 3) is based on four data points. I don't know if this is p-hacking, per se, but it's not a robust result. And not that I give the paper a lot of credence, but it's worth nothing that the overall trend across all pathogens is that masks are ineffective against aerosols. Link two is a news article and contributes no data. Link three is a survey of people self-reporting a bunch of different things, where they've thrown out 32% of the data for non-response, selected the ones who did respond (bias!) and used that to make claims about face masks. Moreover, their data shows that as people wear face-masks more often, their chance of getting Covid goes up! This paper has so many confounders and potential sources of bias that it simply cannot be taken seriously. When I said that the research literature on masks over 2020 hasn't gotten any better, these kinds of papers are exactly what I meant. They're terrible, they're littered with methodological and data analysis flaws, and provide no useful information to the debate. If these "seem clear to you", you don't understand what you're reading and lack the ability to assess research literature. Sadly, top-tier journals publish a lot of garbage, particularly when that garbage is topical and will get press. You cannot use "Nature paper" as a badge of quality. You still have to read and understand the paper.
  - kgarten 5y ago
    in terms of physics I see a good reason to wear a mask. If COVID did not invent a sneaky way to go around that Article 2 has a whole lot of pre-prints with data in the citations ... :) Here's a follow up (also with a lot of paper citations : https://www.nature.com/articles/d41586-021-01394-0 https://www.nature.com/articles/d41586-021-01394-0 Talking with friends who are virologists, they all seem to agree masks help. What's wrong with the articles the nature commentary are based on And articles like that: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0249891 https://journals.plos.org/plosone/article?id=10.1371/journal... https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7883189/#__ffn_sectitle https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7883189/#__ffn_...

by timr 5y ago

nickthemagicman 5y ago

Thanks for posting. No one on the pro-mask side reads scientific papers. They're fascists and want to crush their opposition through controlling the narrative instead of actual science.

kgarten 5y ago

Anecdotal, how do you explain the non existing flue season (last autumn ) and the low incidences in Japan? We got higher rates during the Olympic. I live in Tokyo, Japan and visit US/Europe often. The only significant difference I see is the willingness to wear masks. And there's way less space here (packed subways etc.)

timr 5y ago
Well, any rational conversation about Japan has to start with the observation that cases are at an all-time high right now: https://www.asahi.com/topics/word/%E3%82%B3%E3%83%AD%E3%83%8A%E3%82%A6%E3%82%A4%E3%83%AB%E3%82%B9.html?iref=evb_1 https://www.asahi.com/topics/word/%E3%82%B3%E3%83%AD%E3%83%8... I don't think changing rates of masking can explain that change. > Anecdotal, how do you explain the non existing flue season (last autumn ) and the low incidences in Japan? We got higher rates during the Olympic. I haven't seen any data on flu during the olympics, so I can't comment on that. Covid cases, of course, were shooting up long before the first athletes even arrived in Japan (see above). To answer your question, nobody knows why flu "disappeared" during the last year. My hypothesis is a combination of two things: 1) it didn't disappear, it just spread less due to to the dramatic reduction in international travel (plus maybe closure of schools). 2) we stopped testing for flu at rates necessary to detect it. Our prior surveillance system for influenza was pretty limited, and most of it switched to Covid in 2020. In general, I think people fixate on masks far too much, because they're visible. Even in Japan, what qualifies as a mask would make Americans in the "mask compliant" cities laugh out loud. I routinely see people wearing these on Instagram and on television: https://www.superdelivery.com/product_image/812/8/8128738_1000.jpg https://www.superdelivery.com/product_image/812/8/8128738_10...
- kgarten 5y ago
  anything that interfere with droplet dispersion is better than nothing ... no? https://www.youtube.com/watch?v=pwOwMsCc6NA https://www.youtube.com/watch?v=pwOwMsCc6NA https://www.youtube.com/watch?v=GAvO_QdO9eM https://www.youtube.com/watch?v=GAvO_QdO9eM Seems basic to me ... If the droplets from me don't reach to the first person in the cinema I cannot infect them.
  - belorn 5y ago
    > If the droplets from me don't reach to the first person in the cinema I cannot infect them. It would be nice if that was true. In a small study here in Sweden they tested for covid particles in the AC system, and found particles in every single place they tested. This in a major hospital where everyone are wearing masks, and where the AC is located in the ceiling. The finding was not what the researcher was expecting, especially not in the AC system located on the roof. How much interference a mask has is determined by the leak rating, but for most surgical masks there are no protection for the finer droplets in coughs and sneezes. In a similar style, people though initially that bath houses and saunas would be safe against covid because the large droplets in the humid air would drop quickly to the ground. Later it was generally agreed here that the conclusion was incorrect and all public bath houses and saunas closed. Like with masks, humid air might be better than nothing but you really do not want to be near a person who are sick unless you got yourself an air filter and face shield.
    - kgarten 5y ago
      Yes, that's the point masks are better than nothing. They might reduce the likelihood (without much of a negative impact). That's why we should wear them. A vaccination also just reduces the likelihood you get covid. People can still get it and still spread it, even if they are vaccinated. It just reduces the likelihood and masks might do that as well ...
      - belorn 5y ago
        Yes, through masks don't reduce the likelihood of infection in the same way like vaccinations. The vaccination significant reduce infection rate for the person who takes it. Any secondary effect on other people is the result of the vaccinated person not being sick. Mask on other hand might in a limited way reduce spread if the person who wear it is sick. Masks without intake filters has zero effect on the person who wears the mask. Vaccinations also have requirements with generally 90%+ protection, while masks has anything from 0 to 90% effectiveness in filtering breath emissions. As a effective measure against covid, vaccinations are a much more effective and powerful tool. After two years and in my experience, you can't have large gatherings and expect a low risks. Neither vaccines nor mask nor the combination of both can produce enough of an defense. 2m distancing, washing hands, and keeping human gatherings inside to an absolute minimum is the only way, and then follow up with mass vaccinations. I don't think given current scientific knowledge that one can cheat that process.

srinivgp 5y ago

The paper you linked to says, in its summary section, "For the general public, evidence shows that physical distancing of more than 1 m is highly effective and that face masks are associated with protection, even in non-health-care settings, with either disposable surgical masks or reusable 12–16-layer cotton ones, although much of this evidence was on mask use within households and among contacts of cases." But I assume you mean that the meta analysis didn't claim masks were useless, those three underlying papers did? I'm not sure what those three were, though, maybe I missed it. I found all the papers used but there were like a dozen in the non-health-care setting.

timr 5y ago
That is their interpretation of the meta-analysis, yes ("summary section" == "discussion section"). That is not a statement of fact, but of the authors' opinions about the facts reported. The data stands on its own -- though in this case, since it's a meta-analysis with fancypants statistical re-weighting of the data, the line between "data" and "analysis" is decidedly blurred. > But I assume you mean that the meta analysis didn't claim masks were useless, those three underlying papers did? I'm not sure what those three were, though, maybe I missed it. I found all the papers used but there were like a dozen in the non-health-care setting. The data they have presented, aggregating ~all of the prior research literature on masks, shows a weak effect, at best. Only by mixing data from different settings (mostly hospitals) and different types of masks (from cloth to respirators) and re-weighting the conclusions do they arrive at this claim of even weak effectiveness. Do masks work? Based on the literature, the only honest answer is "maybe they have a small effect, but the evidence isn't very good." Compare this to what you see repeated in the media and by "experts". The truth is...most of these people haven't read the papers, and are just repeating what they've heard.

kgarten 5y ago

Not improved?? I just checked nature... https://www.nature.com/articles/s41591-020-0843-2 https://www.nature.com/articles/s41591-020-0843-2 https://www.nature.com/articles/d41586-020-02801-8 https://www.nature.com/articles/d41586-020-02801-8 https://www.nature.com/articles/s41467-021-24115-7 https://www.nature.com/articles/s41467-021-24115-7 Seems pretty clear to me.

timr 5y ago
The Leung et. al. paper (first link) should never have passed editorial review. Look at figure 1: the only significant result in the entire paper (1a, panel 3) is based on four data points. I don't know if this is p-hacking, per se, but it's not a robust result. And not that I give the paper a lot of credence, but it's worth nothing that the overall trend across all pathogens is that masks are ineffective against aerosols. Link two is a news article and contributes no data. Link three is a survey of people self-reporting a bunch of different things, where they've thrown out 32% of the data for non-response, selected the ones who did respond (bias!) and used that to make claims about face masks. Moreover, their data shows that as people wear face-masks more often, their chance of getting Covid goes up! This paper has so many confounders and potential sources of bias that it simply cannot be taken seriously. When I said that the research literature on masks over 2020 hasn't gotten any better, these kinds of papers are exactly what I meant. They're terrible, they're littered with methodological and data analysis flaws, and provide no useful information to the debate. If these "seem clear to you", you don't understand what you're reading and lack the ability to assess research literature. Sadly, top-tier journals publish a lot of garbage, particularly when that garbage is topical and will get press. You cannot use "Nature paper" as a badge of quality. You still have to read and understand the paper.
- kgarten 5y ago
  in terms of physics I see a good reason to wear a mask. If COVID did not invent a sneaky way to go around that Article 2 has a whole lot of pre-prints with data in the citations ... :) Here's a follow up (also with a lot of paper citations : https://www.nature.com/articles/d41586-021-01394-0 https://www.nature.com/articles/d41586-021-01394-0 Talking with friends who are virologists, they all seem to agree masks help. What's wrong with the articles the nature commentary are based on And articles like that: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0249891 https://journals.plos.org/plosone/article?id=10.1371/journal... https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7883189/#__ffn_sectitle https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7883189/#__ffn_...