Talk:Face masks during the COVID-19 pandemic/Archive 2

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I dont want to even start a editing a medical topic before anyone reverts and mentions

https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD006207.pub6/epdf/abstract

--Stefan-S ^talk 18:16, 8 February 2023 (UTC)

It's a fine source. My only caution would be I notice it's been horribly misused in various social media venues so we would need to be scrupulous in summarizing it to avoid any replay of that. Bon courage (talk) 18:23, 8 February 2023 (UTC)

So you mean, dont say "Masking has proven effective in reducing the transmission of COVID-19 and other airborne illnesses through many studies" when you have a sources that say "Upon our critical review of the available literature, we found only weak evidence for wearing a face mask as an efficient hygienic tool to prevent the spread of a viral infection." or "This systematic review and meta-analysis suggests that several personal protective and social measures, including handwashing, mask wearing, and physical distancing are associated with reductions in the incidence covid-19." or ... Im not sure??? But what I get is you get lots of percent blockage of particles if you wear a mask, if you wear multiple masks it blocks more particles, and if you wear a cloth mask it also blocks particles, and if you if you mandate mask it reduces new infections and mortality, and if you report that you wear a mask your risk of infection is reduced by 10%"? I get it!! :-) I like trying to follow the sources and not try to interpret them!!!  :-) ~~~ --Stefan-S ^talk 19:00, 8 February 2023 (UTC)

Well, it's necessary to read with understanding. Bon courage (talk) 19:05, 8 February 2023 (UTC)

That efficacy section could probably do with a bit of reorganization, perhaps trimming the 'X has not been studied as of Y date' stuff, and then having it go over the various systematic reviews and meta-analyses in a sensible order and attributing the various findings carefully if not done already. The addition of the 2023 Cochrane review was well done, but the surrounding material and order could be improved IMO. Crossroads ^-talk- 19:07, 8 February 2023 (UTC)

Yes, now it is not consistent, need to add the different view of Cochrane throughout the article to make it consistent, inclusive of the lead. --Stefan-S ^talk 19:17, 8 February 2023 (UTC)

@Bon courage, since the cochrance review is clear about the issue of incorrect masks use we put that clearly when we say that mask might not have little or not impact (sorry I mean inconclusive which I guess means that same??), but since many of the rest of the other sources (built on the same RCTs??) did not say that we dont bother to say that they might be equally flawed, I know the rules, but I question how we implement them .....? --Stefan-S ^talk 19:50, 8 February 2023 (UTC)

Other studies are not built "on the same RCTs". Bon courage (talk) 20:20, 8 February 2023 (UTC)

IIRC variation between reviews in part has to do with whether

observational studies and other non-RCTs are included; additionally, some reviews during Covid may not have included pre-Covid studies on other viruses such as flu, but the 2023 Cochrane review did. Limitations, of course, apply to those earlier reviews as well; if that is to be mentioned for this review it should also be done for those (e.g. confounders in observational studies). We also have to be very careful it isn't undue or OR. For instance, it's possible that 'few people using masks correctly' is an important thing to account for in determining efficacy of population-level interventions. Crossroads ^-talk-

01:08, 9 February 2023 (UTC)

For Cochrane, is was significant enough to be raised in the first sentence of the authors' conclusions, so it would be odd to omit. We should probably also mention their overall doubts about evidence quality. Bon courage (talk) 04:02, 9 February 2023 (UTC)

The authors are pretty clear - the studies they reviewed were unreliable and they can't draw a conclusion: "The high risk of bias in the trials, variation in outcome measurement, and relatively low adherence with the interventions during the studies hampers drawing firm conclusions." - i.e. the research sucked and they can't make heads or tails out of them. MartinezMD (talk) 04:05, 23 February 2023 (UTC)

That seems to be reading a lot more into that sentence than is warranted, especially since their conclusions still state a lot more than that. Crossroads ^-talk- 05:43, 23 February 2023 (UTC)

"There is uncertainty about the effects of face masks. The low to moderate certainty of evidence means our confidence in the effect estimate is limited, and that the true effect may be different from the observed estimate of the effect"

"Key messages

We are uncertain whether wearing masks or N95/P2 respirators helps to slow the spread of respiratory viruses based on the studies we assessed"

Well how about these 2 ^ additional sentences? They're saying the same thing. They can't tell from the studies they reviewed. MartinezMD (talk) 05:53, 23 February 2023 (UTC)

The following text I added about the Cochrane review has been reverted twice, with the second revert requesting a discussion.

With low-to-moderate certainty in the evidence and limited confidence in the effects, the review concluded that the use of surgical masks probably makes little or no difference in preventing COVID-19-like and flu-like illnesses. Without evaluating the effect of N95/P2 masks specifically against COVID-19, the review concluded that they make little or no difference in preventing flu, but may be effective in preventing flu-like illnesses in general. The review found a significant 11 to 14% reduction in the incidence of respiratory illness in general with better hand hygiene.

Everything here was taken from the main results and conclusions sections of the study (section Medical/surgical masks compared to no masks is particularly relevant as it is the only result specific to COVID-19). What is wrong with it? These results are presented next to moderately tight confidence intervals and estimated relative risks near 1.00. Fernando Trebien (talk) 14:47, 6 May 2023 (UTC)

See many discussions above, but putting that the review concluded masks might not be good at "preventing COVID-19-like and flu-like illnesses" is not appropriate for what was a population-level review. Do you think medics are going to stop using PPE in a clinical setting? What we have is a good summary. Bon courage (talk) 14:58, 6 May 2023 (UTC)

I don't think doctors would stop using protective masks, that would be irresponsible as they prevent the transmission of many diseases, although the same review surprisingly says that Restricting pooling to healthcare workers made no difference to the overall findings. about the effectiveness of N95/P2 masks against laboratory-confirmed influenza infection. I understand that masks are effective against various diseases, but to different degrees, and in the case of these respiratory diseases, the study concludes that they are probably little or not at all effective at the group level. We can (and probably should) mention Cochrane's statement on the interpretation of these reported findings. How about we change the use of surgical masks with the use of surgical masks by the general population in everyday activities? --Fernando Trebien (talk) 17:03, 6 May 2023 (UTC)

• The study looked at the effectiveness of interventions to promote the use of masks, for example handing out free masks (but, notably, not mask mandates). So in the above example the lack of effectiveness might simply be because participants didn't wear the free masks, rather than them being ineffective when they were worn.
• I'm against directly quoting the study because it's been widely misinterpreted in the media and elsewhere (as the Cochrane statement says, some of the wording is open to misinterpretation). I think the current wording in the article is fine, or we could directly quote the Cochrane statement: "the review examined whether interventions to promote mask wearing help to slow the spread of respiratory viruses, and that the results were inconclusive".

PieLover3141592654 (talk) 22:06, 6 May 2023 (UTC)

It looks like Cochrane will reword the plain language summary to avoid misinterpretation,^[1] so perhaps we should wait. But I understand that the results of an intervention are still relevant in the sense that, if it does not work due to low adherence, then it's an ineffective policy, better focus on hand washing and ventilation. --Fernando Trebien (talk) 19:54, 9 May 2023 (UTC)

Yes, I think waiting makes sense. Agree with you that this study is relevant for assessing the effectiveness of interventions. Although given "the results are inconclusive", all it really tells us is we need more/better RCTs. PieLover3141592654 (talk) 07:50, 13 May 2023 (UTC)

Is

Masking has proven effective in reducing the transmission of COVID-19 and other airborne illnesses through many studies.

consistent with the Cochrane review? Talpedia (talk) 06:33, 7 March 2023 (UTC)

Yes, though it's complicated. Are we talking population level or in a clinical setting for example? Bon courage (talk) 07:23, 7 March 2023 (UTC)

Cochrane seems to focus specifically on reducing the rate of illness by the person implementing the intervention (they included hand washing), while the various observational studies cited in the lead tend to focus on masking as source control. It seems we may want to clarify our phrasing of the Cochrane review to clarify this: A 2023 systematic review from the Cochrane Collaboration said the evidence from randomized controlled trials was still inconclusive over whether masking prevented the spread of viruses, including SARS-CoV-2, through a population. Cochrane seems much more narrowly focused on the individuals wearing the masks, and only considered RCTs (with the population masking for source control support coming mostly from observational studies, as RCTs on a population in this way is difficult to perform), so using their term "spread" may be misleading compared to what they actually measured which was "infection".

I'll also note, the above text mentions a 2023 update, but it's cited to the 2020 version which says: The evidence summarised in this review does not include results from studies from the current COVID‐19 pandemic. I'll update to the current citation. Bakkster Man (talk) 14:04, 7 March 2023 (UTC)

I guess I feel the lead should be something like "Masking has proven effective in reducing the transmission of COVID-19 and other airborne illnesses through many studies when used effectively, but evidence is inconclusive about its effectiveness when used amongst the public." since I suspect the reader is apt to read the lead and think "ah that means mask mandates work" (should this be consistent with the sources). Talpedia (talk) 02:53, 8 March 2023 (UTC)

I guess the take away is "masks work, but it's hard to get people to use them conistently". Talpedia (talk) 02:56, 8 March 2023 (UTC)

Yes, and for other reasons[1] this particular 2023 Cochrane review needs to be treated carefully. Bon courage (talk) 05:49, 8 March 2023 (UTC)

Sure, though I would counter that all post covid sources related to masking need to be treated carefully! Talpedia (talk) 09:26, 8 March 2023 (UTC)

That source isn't a

WP:MEDRS and is not even close in weight to a Cochrane review (or any academic review). I strongly believe we should stick closely to what the MEDRS reviews say, and disregard all the noise in nonacademic sources from loud unrepresentative people who hear what they want to hear, all too often based on their priors and politics. That includes both the 'Cochrane proved that masks don't work ever' crowd and the 'Cochrane tells us nothing and mask efficacy is unquestionable' crowd. Crossroads ^-talk-

02:26, 9 March 2023 (UTC)

I think that's the conclusion from the other sources we have, masks reduce community spread via source control and efficacy is reduced when worn inconsistently. The Cochrane review concludes that the studies they analyzed didn't provide effective respiratory protection, which was only ever a hoped for secondary benefit (and as Bon courage links, might be an underestimate of efficacy due to including studies where masks were only worn sometimes). Bakkster Man (talk) 14:05, 8 March 2023 (UTC)

Hmm? The Cochrane review seems to be about "spread" and "the community", not just personal protection. Crossroads ^-talk- 02:28, 9 March 2023 (UTC)

They use the words "spread" and "community", but only analyzed RCTs evaluating whether the user of the intervention was infected. Which, in the plain language we should be using on the article, would be confusing to mix with the way our other sources define community spread and and use it to describe source control. And we do have MEDRS sources indicating based on observational studies that masks are effective there.

And for clarity, Cochrane does appear to suggest that due to a lack of RCTs they're not evaluating community masking, only individual masking. Several specific research gaps deserve expedited attention and may be highlighted within the context of the COVID‐19 pandemic. The use of face masks in the community setting represents one of the most pressing needs to address, given the polarised opinions around the world, and the increasing concerns over widespread microplastic pollution from the discarding of masks (Shen 2021). Both broad‐based ecological studies, adjusting for confounding and high quality RCTs, may be necessary to determine if there is an independent contribution to their use as a physical intervention, and how they may best be deployed to optimise their contribution. Bakkster Man (talk) 13:56, 9 March 2023 (UTC)

I think there's a lot of possibility to improve and update that sentence. I would suggest something like the following citing the existing sources and Cochrane; of course this is a starting point and it can be tweaked: Reviews of various kinds of scientific studies have concluded that masking is effective in protecting against COVID-19, though the evidence from randomized controlled trials is inconclusive as to whether mask policies reduce spread on a population level. Crossroads ^-talk- 02:47, 9 March 2023 (UTC)

Since the Cochrane review explicitly says they aren't investigating community masking, I think it would be better to cite other sources we have and say something like "Reviews of various kinds of scientific studies have concluded that masking is effective in protecting the individual against COVID-19. Various

WP:MEDRS. Sometimes they hedge their bets too much. We have very high quality sources which say community masking reduces spread. If you really want we could also say: though the evidence from randomized controlled trials has been inconclusive as to whether mask policies reduce spread on a population level. — Shibbolethink ^{(♔ ♕}

) 19:48, 9 March 2023 (UTC)

I added it as you suggested, including the bit about the Cochrane review. It's still a very strong source in weight, and it's worthwhile to relay it accurately and in context of other types of research findings rather than simply ignore it. Crossroads ^-talk- 18:06, 11 March 2023 (UTC)

• Cochrane are now walking parts of this review back.[5] What a mess. Bon courage (talk) 07:15, 13 March 2023 (UTC)

  The SBM piece gives some really good context. The direct Cochrane statement is here. 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. Given the limitations in the primary evidence, the review is not able to address the question of whether mask-wearing itself reduces people's risk of contracting or spreading respiratory viruses. Bakkster Man (talk) 12:55, 13 March 2023 (UTC)

I already mentioned this is the section above ("New source MEDRS?"). The studies the Cochrane review used were poorly executed "There is uncertainty about the effects of face masks. The low to moderate certainty of evidence means our confidence in the effect estimate is limited, and that the true effect may be different from the observed estimate of the effect". imho the NYT opinion piece was irresponsible in sensationalizing its title and providing a poor description of the review. We need to write the article carefully and write statements that are accurately supported by the sources. MartinezMD (talk) 13:21, 13 March 2023 (UTC)

I think the SBM link above does a good job of giving compelling reasons for this, both that the lead author tends to sensationalize and mischaracterize his conclusions in interviews where there isn't peer review (i.e. There is just no evidence that they [masks] make any difference. Full stop.), and the tendency for evidence-based medicine to favor RCTs to a fault (All you needed was for Tedros [from WHO] to declare it’s a pandemic and they could have randomised half of the United Kingdom, or half of Italy, to masks and the other half to no masks. But they didn’t. Because, as Gorski rightly points out, this would be highly unethical, especially in the midst of an international public health emergency). And yes, making sure we summarize this review as per the clarification provided above (it's inconclusive), and not superseding our other MEDRS sources which were able to reach conclusions. Bakkster Man (talk) 13:47, 13 March 2023 (UTC)

Since we're meant to be summarizing "accepted knowledge", I'm not sure about using this source at all. Bon courage (talk) 13:49, 13 March 2023 (UTC)

I'm a bit more circumspect on removal on that reason alone. An inconclusive result is still a finding, as long as it's presented accurately and neutrally. The accurate and neutral part being the challenge for us here. I would agree it's not our strongest source on the topic by a long shot, and if included should be presented as such; that in addition to the other studies which did find community masking to be effective in limiting community spread, the 2023 update to a Cochrane Reviews analysis did not reach a conclusion on the efficacy of masks in preventing the wearer's infection. If we can find a reliable source providing additional context of why the RCTs and/or focus on infection prevention might be less certain than the source control observational studies used elsewhere (I don't think SBM is the right source to cast doubt on a peer reviewed systemic review), that would be ideal. Bakkster Man (talk) 14:23, 13 March 2023 (UTC)

Agreed regarding SBM being insufficient to cast doubt and on including the inconclusive Cochrane result neutrally. As far as I can tell our use of it from the beginning has been in line with what the 'clarification' from the Cochrane organization says, which indicates to me the success of the approach of sticking closely to the MEDRS themselves and ignoring the noise like the one author's media comments or that NYT oped that exaggerated the result. Crossroads ^-talk- 04:51, 14 March 2023 (UTC)

P. S. Having read the SBM article, while it makes some good points, I find it rather concerning that the framing is basically about how evidence-based medicine (EBM) is a bad paradigm and touting instead their paradigm of "science-based medicine". Looking these phrases up on Google Scholar, EBM seems to be widespread and mainstream, while the SBM term barely exists outside of Gorski and Novella's site. I know SBM (the site) is often used for countering alternative medicine, but that in particular sounds a lot like fringe theorists who complain about the mainstream ignoring their pet idea. Just because some of the arguments made around RCTs and masks are bad or that other evidence should be considered in a pandemic doesn't mean masks or other NPIs shouldn't be subjected to RCTs; indeed, a few were done, and more were done prior to Covid for other respiratory viruses.

It also seems unlikely that an article by Gorski on a site on which he is an editor actually receives meaningful editorial review outside of himself, thus making it a

WP:SPS. Bottom line, though - we should stick to what Cochrane themselves say (along with other MEDRS reviews) and ignore the misleading media commentary. Crossroads ^-talk-

05:42, 14 March 2023 (UTC)

The point was that Cochrane themselves were issuing clarifying statements, and that there was significant pushback from multiple sources (e.g. NYT). The faults or not in EBM are a side issue. Bon courage (talk) 07:20, 14 March 2023 (UTC)

Agreed, whether or not EBM as practiced leaning almost solely on RCTs is an explanation for why they came to a different conclusion, but this article doesn't need to be that broad in its description. It's good background information, but not necessarily appropriate for the article. Bakkster Man (talk) 13:06, 14 March 2023 (UTC)

No indeed. I only linked SBM because it was a good overview with links to the various other publications. I'm not expecting for this article to launch into a discussion about the basis of medical evidence! (Incidentally there have been discussion at WPMED about the weight to be given to SRs and meta-analyses, and Cochrane in particular. It's not like they're quite the 'golden' sources there are sometimes said to be). Bon courage (talk) 13:12, 14 March 2023 (UTC)

I think it's important to note that the Cochrane meta-analysis was a combination of results from influenza and COVID illnesses. If they had restricted their meta-analysis to COVID RCTs, they would have got the same result that the other systemic reviews of masks on COVID had got.

Now they might be right that it is better to pool influenza and COVID results, and due to the paucity of COVID RCTs, that might be the only good choice if you restrict to RCTs. (In some sense that wasn't even a choice the Cochrane study made, because they were updating an earlier study.) The Royal Society systemic review includes observational study COVID results for that reason.Dan88888 (talk) 16:44, 2 September 2023 (UTC)