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Cochrane review is out and masks have weak evidence that they are not effective

vinayprasadmdmph.substack.com

This one is against rationalists because when Scott wrote his review that masks could be effective many of us trusted it.

I don't blame Scott for failing this one because doing review of hundreds of studies is hard and one person can hardly do it. But this clearly shows that rationalist way of thinking has no special formula, they can be easily mistaken and fall by accepting general consensus just like any other person.

I was impressed when Scott did his review about masks. I trusted it because there was no other clear evidence available. Cochrane hadn't done its review yet and NICE guidelines were silent on the issue. We vaguely knew from previous studies that masks are not effective, The WHO had said so. Suddenly everyone flipped and it was not because the evidence had changed. We simply wanted to believe that masks work and we mocked those who said “no evidence that masks help”.

Even with the belief that masks work, I never wanted mask mandates. I preferred recommendations only, so that no one was penalized or prohibited entry, travel etc if one doesn't want to wear mask. Scott unwillingly had been a catalyst for governments to introduce mask mandates and all this heavy handed approach has been for nothing.

Now we are back to square one, the evidence about masks is weak and it does not support their use even in hospital settings. We can all reflect now what happened in between during these 2 or 3 years. When I realized that Scott's review is clearly insufficient as evidence, I asked some doctors if they have any better evidence that masks work. Instead of getting answer I was told not to be silly, parachutes don't need RCTs and accused me of being covid denier for nor reason. Many so-called experts were making the same mistake as Scott by looking at the issue too emotionally. It is time to get back to reality and admit that it was a mistake and we should have judged the issue with more rational mind.

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Cochrane's own conclusion says:

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.

When you look at the included studies, it's not hard to see why. For one, many of these studies pre-date COVID and focus on ILI. In addition, the ones that I've looked at so far in their summary table are not measuring the effectiveness of masks. They're measuring the effectiveness of trying to get people to wear masks, if they aren't already. For example, the second study listed, Alfelali 2020, notes that the test group had about 25% "daily" mask use and 13% in the control group (it was also a study of ILI, with data gathered from 2013 to 2016). On the flip side, we have MacIntyre 2015 reporting over 50% adherence for both cloth and medical masks (which was on healthcare workers, clearly a different population). Given the obvious issues with both noncompliance and heterogeneity, it's not exactly surprising that they got a null result. It looks to me like only 2 of the included 12 studies were even specific to COVID.

From the point of view of a policymaker, this (arguably) makes sense, although you would still prefer to have separate studies of how people respond to wearing masks, and then how effective they are if you wear them. Both of those things are likely to change based on location and population. From an individual point of view, you should care much more about how effective masks are if you wear them consistently and interact with other people wearing them.

The linked blog post is greatly exaggerating the strength of this evidence, and clearly is trying to push a political agenda by downplaying these limitations and ignoring any nuance.

The linked blog post is greatly exaggerating the strength of this evidence, and clearly is trying to push a political agenda by downplaying these limitations and ignoring any nuance.

There was once I time I believed there are people who aren't doing that. Then there was a time I could at least pretend. We're so far past that point it's not even funny.

Can you show how what they're doing is worse then what the people who pushed through mask mandates did? Otherwise there's nothing interesting about that sentence.

Can you show how what they're doing is worse then what the people who pushed through mask mandates did?

No, such a task is impossible. "People who pushed through mask mandates" is an enormous and varied group. It's almost certainly the case that some of them insisted the evidence is overwhelming, while others were more sanguine.

Otherwise there's nothing interesting about that sentence.

The link posted here wasn't a link to someone claiming that masks are definitely foolproof and should be enforced during COVID outbreaks. If someone makes that post with flimsy evidence (and I see it) I'll call them out too. I oppose bad arguments, regardless of the conclusion.

So you were passionately arguing against mask mandates when they were being pushed?

What does that have to do with anything? Do you actually care about the evidence, or are you just looking for gotchas?

Well, it would show that you oppose bad arguments regardless of conclusions.

Do you actually care about the evidence

Sure, I'd love to see evidence that would justify the actually implemented policies, and the censorship of dissent.

I did oppose mask mandates, but I could also just be saying that now because this entire forum isn't that old.

Anyway, I don't get the sense you're acting in good faith, so this is probably where I bow out of this conversation.