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Surgical masks reduce Covid-19 spread, large-scale Stanford study shows

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Re: Surgical masks reduce Covid-19 spread, large-scale Stanford study shows

#131

Post by jasonlaramburu »

polote wrote: post #127
ch4s3 wrote: post #3

> There were significantly fewer COVID-19 cases in villages with surgical masks compared with the control villages. (Although there were also fewer COVID-19 cases in villages with cloth masks as compared to control villages, the difference was not statistically significant.) This aligns with lab tests showing that surgical masks have better filtration than cloth masks. However, cloth masks did reduce the overall like…

At the end of the day if the reduction is 11%, even if that works (because that reduce by 11%) that is still useless in order to control the epidemic. Unless we find 10 measures like that. But what they show is probably not the same that the impact of mask mandate or an `always wear mask` at the personal level. So not much is applicable about that study. Only that mask kind of reduce covid spread

Anyone who is legitimately concerned about COVID transmission should be wearing at least a KN95 mask. It would be interesting if the study had compared effectiveness against higher performance masks and respirators.

Re: Surgical masks reduce Covid-19 spread, large-scale Stanford study shows

#132

Post by hncurious »

douglasisshiny wrote: post #13
exabrial wrote: post #6

This is truly great news, as we've need some controlled studies. However, _mandates_, literally threatening people with police violence, bodily or financial harm, is not the correct way forward. I think the best solution is improved mandates for airflow. It's a lot easier to improve airflow in a building than it is to police and enforce a mask mandate.

>However, _mandates_, literally threatening people with police violence, bodily or financial harm, is not the correct way forward. Maybe I'm missing something, but is this actually a thing? Who in the mainstream proposing police violence, bodily or financial harm? The worst I've heard (in the U.S.) is that a business may not allow you to enter if you're not wearing a mask, which is well within their right and reasona…

It's gone beyond proposal to actually happening in some places. There are some scary examples coming out of Australia.

https://youtu.be/XOKPtYdDh20?t=232

https://twitter.com/Lukewearechange/status/14330657788032655...

Re: Surgical masks reduce Covid-19 spread, large-scale Stanford study shows

#133

Post by alecst »

My first reaction was to consider this as pretty damning of mass use. But when I considered it more I don't think the study is as damning of masks as it is of mask mandates.

The problem is only ~30% more people wore masks in the intervention arm of the study. So the best possible outcome, removing 30% from the infection group entirely (essentially taking them out of the population -- a "perfect spherical mask" approximation), is a 30% reduction in cases. Which is substantial, but no one expects masks to be that effective anyway. 11% seems a reasonable ballpark.

If everyone had worn masks it would have been easier to measure the effect of just the masks.

Still, it's worth considering the big picture. If mask mandates aren't enforced, they're not worth a whole lot. Especially if you have limited political capital to spend.

Re: Surgical masks reduce Covid-19 spread, large-scale Stanford study shows

#134

Post by clairity »

timr wrote: post #51
slg wrote: post #16

Earlier quoted context omitted.

>It's surprising to me that cloth masks can't even do the 11% of surgical masks. Just want to add clarification here. The 11% number is the community impact of the programs designed to increase mask usage. It is not the effectiveness of a mask on an individual level. That number will be much higher since as you said a number of people didn't/don't comply at a societal level.

> That number will be much higher since as you said a number of people didn't/don't comply at a societal level. ...or it will be lower. The study confounds the effects of distancing and mask-wearing. Distancing was higher in the surgical mask cohort. Also, as others note, the confidence interval for the surgical mask group overlaps zero. You can't rule out that the observed effect is due to chance.

yes, distancing does most of the work in most common situations. a mask can only work when conversing closely for a time indoors. otherwise masks do nothing, no matter the filtration rate of the mask, because there's nothing to filter in the first place. distancing is a more universal and sensible mitigation (we're distanced from nearly all of the world population all the time).

this is why mask mandates, as currently constructed, are misguided and ignorant at best. the mandate should be to wear a mask when you're intimately sharing air (within ~3ft/1m) with another person indoors. the reason we don't have that sort of mandate is because it would mean we'd have to wear them around friends and family rather than those gross strangers who are out to kill us with their ignorance and malice (they're not).

this is also why the current mandates for restaurants (and most retail) makes no sense, as we're only going to be intimately sharing air with our friends and family in those places anyway.

Re: Surgical masks reduce Covid-19 spread, large-scale Stanford study shows

#135

Post by dragontamer »

cfn wrote: post #54
jerf wrote: post #29

Earlier quoted context omitted.

I know it's easy to get cynical about "sampling" when you see a stream of studies sampling populations of millions with n = 12 and getting p values just barely considered "significant", but that's not the fault of "sampling". That's just... gathering no data, basically, or if you prefer, going through the motions of gathering data without actually doing it.

I am not arguing with the method, I only think the language of the paper is misleading to the point that the parent commenter aparently thinks they actually analysed hundred of thousands of subjects when they just extrapolated their observations to that number. It may even be right and significant but that is not my point.

I've reread the article + paper with your discussion in mind, and I agree with you. It seems misleading, and I failed to understand the study from the headline / abstract.

Its not a "bad" study per se, but its definitely entering clickbait. I'm still happy they conducted the study and presented their research.

Re: Surgical masks reduce Covid-19 spread, large-scale Stanford study shows

#137

Post by packetlost »

jasonlaramburu wrote: post #130
belorn wrote: post #124

Its interesting that the article do not mention a rather interesting finding in the study. For the age groups of Why aren't masks effective to reduce the spread for that age group? The discussion part of the study don't explore it. Is the distancing behavior of people aged 50 or higher different than those below? I would like to see further studies being done on the younger demographic in order to explain why the dat…

Maybe lower mask adherence among younger people or different behaviors-- older people in villages might stay at home more.

if the latter is true, then wouldn't that be an indicator that masks do not, in fact, work as well as thought?

Re: Surgical masks reduce Covid-19 spread, large-scale Stanford study shows

#138

Post by otabdeveloper4 »

dragontamer wrote: post #2

> The researchers enrolled nearly 350,000 people from 600 villages in rural Bangladesh Wow. I was about to complain about "small n", but... an experiment of this size is not small at all. Congrats on the researchers on doing such a big study!

Size of N isn't the issue, controlling for confounding variables is.

Re: Surgical masks reduce Covid-19 spread, large-scale Stanford study shows

#139

Post by nradov »

bgorman wrote: post #111

The problem with this mask business is it treats masks as the only variable. The United States is incredibly unhealthy and most people do not get enough exercise or spend enough time outdoors. It would not surprise me if governments would obtain better results by telling citizens to exercise regularly and eat healthy. Instead it seems like governments are doubling down on a strategy on scaring/bullying out of shape c…

Maintaining the recommended level of physical activity cuts COVID-19 death risk by 4× compared to being sedentary.

https://bjsm.bmj.com/content/early/2021/07/21/bjsports-2021-...

And before anyone claims that it's just a correlation, please read the whole paper. The authors did a good job of establishing causality.

Re: Surgical masks reduce Covid-19 spread, large-scale Stanford study shows

#140

Post by jacquesm »

belorn wrote: post #124

Its interesting that the article do not mention a rather interesting finding in the study. For the age groups of Why aren't masks effective to reduce the spread for that age group? The discussion part of the study don't explore it. Is the distancing behavior of people aged 50 or higher different than those below? I would like to see further studies being done on the younger demographic in order to explain why the dat…

Compliance.
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