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0 pointstimr4y ago0 comments

> There was never any significant evidence masks for the public don't work, on the contrary there was at least some flu-based evidenced that they were beneficial, but at best you could say "we don't know"

We aren't supposed to make decisions on medical interventions based on "evidence that X doesn't work". Otherwise, we'd default to just doing stuff until we had evidence that it was worse than doing nothing at all. Literally every failed drug ever tested had a biologically plausible reason for starting the test, and yet we know that most drugs don't work when you take them out of the lab!

Saying that there were some papers out there recommending masks is beside the point, because you can find papers recommending lots of things that don't work. Pretty much anything, in fact. We can see the double-standard at play directly with the Ivermectin debate. Public masks and Ivermectin both have an evidence base of low-quality data, with weak effect sizes and huge error bars overall, and a clear bias of the strongest reported effect toward the lowest-quality evidence. But one is evil and the other is magic, depending on your politics.

To take it back to the subject of the OP, here we have two issues that are fundamentally nuanced (the evidence bases are ambigious, at best), and collapsing the range of allowable communication to "you must do X!" leads to obviously wrong outcomes no matter what you do. So maybe we shouldn't be doing anything at all? Or maybe...maybe...we could try to get answers with experiments, instead of just making things up and asserting that we're right?

For whatever it's worth, I recommend this paper as a balanced, comprehensive review of mask literature (not just cloth, though that is the title). You will not find a more complete treatment of the data for public masking:

https://www.cato.org/sites/cato.org/files/2021-11/working-pa...

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hn_throwaway_994y ago

To be clear, I'm not arguing that health care orgs should have recommended masks early in the pandemic. What I am saying is their adamant declarations of "masks don't work for the public", which note is an affirmative declaration, were false, and never had any supporting evidence. My question is about whether this "simpler, un-nuanced" explanation in fact complicated things in the longer run.

timrOP4y ago

Yes, I know. We're basically in agreement on the broader points, but I don't agree with your second sentence, and you seem to have the opposite bias in terms of how to act under uncertainty:

> What I am saying is their adamant declarations of "masks don't work for the public", which note is an affirmative declaration, were false, and never had any supporting evidence.

There's no such thing as an affirmative declaration of the null hypothesis. You either have proof that something works, or you do not. If you do not have evidence that X works, or the evidence is ambiguous, your conclusion is the null hypothesis (that X doesn't work)...but that doesn't mean that you have to scream it from the rooftops. You can just say "we don't know; the evidence is poor."

The only accurate thing you can say in the "mask debate" is that strong declarations both ways are wrong. The original declarations were wrong, and the declarations now are also wrong. If you look at the data you can't judge either way (with the exception of cloth masks, which are looking quite poor), and so we must equivocate.

The only way you can possibly go on this issue and still be correct is to use nuance. And if you do that, then it's a question of how you use medical evidence to advocate for interventions.

comp_throw74y ago

> If you do not have evidence that X works, or the evidence is ambiguous, your conclusion is the null hypothesis (that X doesn't work)

No??? This is what having a prior is for. In this case, the prior was the mechanistic model which told you with reasonable confidence that masks would work in the slices of worlds where the primary mode of transmission was one mitigated by mask-wearing. We do not in fact live in a state of helplessness absent a double-blind peer-reviewed RCT; you will actively come to incorrect conclusions if you refuse to use your existing models & knowledge of the world to draw conclusions about the likelihoods of various outcomes.

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hn_throwaway_994y ago

> There's no such thing as an affirmative declaration of the null hypothesis.

I strongly disagree, epistemologically speaking. You can run repeated tests and then conclude an intervention is successful. You can also run repeated tests and conclude an intervention is not successful - as you put it, no better than the null hypothesis. Or, finally, you can have just not run tests at all. There is a difference between the second and third states, and health authorities implied the second state when the third state was far more accurate.

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wrp4y ago

For practical purposes, there has to be a point where "we saw no evidence that X works" is considered equivalent to "X doesn't work."

j / k navigate · click thread line to collapse

0 pointstimr4y ago0 comments

https://www.cato.org/sites/cato.org/files/2021-11/working-pa...

0 comments

hn_throwaway_994y ago

timrOP4y ago

Yes, I know. We're basically in agreement on the broader points, but I don't agree with your second sentence, and you seem to have the opposite bias in terms of how to act under uncertainty:

> What I am saying is their adamant declarations of "masks don't work for the public", which note is an affirmative declaration, were false, and never had any supporting evidence.

The only way you can possibly go on this issue and still be correct is to use nuance. And if you do that, then it's a question of how you use medical evidence to advocate for interventions.

comp_throw74y ago

> If you do not have evidence that X works, or the evidence is ambiguous, your conclusion is the null hypothesis (that X doesn't work)

1 more reply

hn_throwaway_994y ago

> There's no such thing as an affirmative declaration of the null hypothesis.

1 more reply

wrp4y ago

For practical purposes, there has to be a point where "we saw no evidence that X works" is considered equivalent to "X doesn't work."

j / k navigate · click thread line to collapse