[Raev]

Originally Posted by Ennewi [You must be logged in to view images. Log in or Register.]

IIRC Raev made the error of equating weather with climate change in a thread a few years back and everyone made sure he never forgot it, myself included.

Probably you mean this. I'm not particularly proud of that little zinger at the end in hindsight, but I don't think the actual post is wrong. In any case, I hope we can confine our discussions to masks today!

Originally Posted by Ennewi [You must be logged in to view images. Log in or Register.]

That one was shown to be more effective than the other implies that either would have been favorable over none at all.

This is clearly wrong: in some cases there is a minimum requirement for any action to be beneficial. For example, just because a cloth bag can hold a bowling ball but a plastic bag breaks does not mean that using the plastic bag is better than carrying the bowling ball with your bare hands.

Originally Posted by Ennewi [You must be logged in to view images. Log in or Register.]

I am still reading through the Denmark link

Cool; I hope you enjoy it! And I hope I am not being too greedy when I ask you to consider reading the link I posted earlier about the doctors in surgery. It's short. However, I thought I'd take a look at https://www.pnas.org/content/118/4/e2014564118 and quite frankly . . . this is a classic example of politicized science. Let's take a look at some of the quotes:

Therefore, we should not be surprised to find that there is no RCT for the impact of masks on community transmission of any respiratory infection in a pandemic.

I have to confess this sentence made my blood boil. This, right here, is political science. 'Hey, all previous work on masks not working on viral transmission? That doesn't matter! We are in a pandemic. Why are we in a pandemic? We say so!' and then, 'Oh by the way, without an RCT we cannot rule out millions of potential causes that might bias our results. No problem! We're in a pandemic! It's SCIENCE because we say it is!' If there is one thing I hope we can agree on it is that this paper is written by twits.

It found that “in an adjusted analysis of compliant subjects, masks as a group had protective efficacy in excess of 80% against clinical influenza-like illness.” However, the authors noted that they “found compliance to be low, but compliance is affected by perception of risk. In a pandemic, we would expect compliance to improve.” In compliant users, masks were highly effective at reducing transmission.

Again, this is simply dishonest because they are attempting to make it seem that compliance causes protection, when most likely the causality runs in the OTHER direction: people stopped using the masks because they got sick!

That review concluded that “there was insufficient evidence to provide a recommendation on the use of facial barriers without other measures.”

Just throwing this out there; 1/3 of the review papers they quote disagrees with them. No effort is made to refute this opinion.

Overall, direct evidence of the efficacy of mask use is supportive, but inconclusive. Since there are no RCTs, only one observational trial, and unclear evidence from other respiratory illnesses, we will need to look at a wider body of evidence.

So even the authors admit that their cherry picked studies are not conclusive.

Consider, for instance, the impact of source control: Its effect occurs to other individuals in the population, not the individual who implements the intervention by wearing a mask.

This, by the way, is the main potential flaw in the Danish study. This past year has been the first time that government succeeded in convincing entire communities to wear masks.

We need to consider first principles—transmission properties of the disease, controlled biophysical characterizations—alongside observational data, partially informative RCTs (primarily with respect to PPE), natural experiments (26), and policy implementation considerations—a discursive synthesis of interdisciplinary lines of evidence which are disparate by necessity

Translation: we are about to crank the bullshit level up to 11, but hey, we're SCIENCE. I can only repeat that all of these after the fact observational studies are garbage. There are a million different reasons why COVID deaths can be lower in a particular nation. The biggest one, by the way, is simply fraud. Unless you seriously believe the Chinese numbers . . .

We recommend that public officials and governments strongly encourage the use of widespread face masks in public, including the use of appropriate regulation.

And boom, the money shot. Totally unwarranted by the actual body of the paper, but everyone involved is now sure to get their next $ million grant form NIH.

I hate writing these choppy usenix style point by point refutation posts. Anyway, I hope you can see why I claim that this is an opinion piece, not science.