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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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Most cars didn't have seatbelts then. Some of those cars are still running and it is legal to drive them without seatbelts.

RCT could be easily made by manufacturing a car with two models that are different only by presence of a seatbelt and randomly shipping to different dealers. If the car had a seatbelt, a dealer is obliged to explain a buyer how to use it properly. The car could have a mechanism installed that warns if the seatbelt is not in use and the dealer warns that defeating this measure will void the warranty. The compliance rate would be at least 50%. Then you just collect statistics from road accidents and related injuries. I am sure very soon this experiment would be stopped by an ethics committee because the seatbelt group would have huge difference that further studies would be unethical.

Maybe people who study road safety used a similar setup by comparing one model with a seatbelt to a different model without a seatbelt. It has some bias as assignment is not random and both groups can be different, for example, one model can be chosen by more careful drivers etc. It is very hard to control for all these factors afterwards. But even then they saw such a massive difference in injuries that could be explained only by seatbelt use, that it was made mandatory. It is easy to make mandatory rules in driving because most things in driving are mandatory, you have to stop at red light etc.

But the absence of RCTs and irrefutable evidence could be a minus because it was harder to explain people why seatbelts are protective. Many people said that seatbelts will protect you in minor accidents but in major crashes they would make you more likely to die. That's why we need a good evidence that seatbelts have a total protective effect from deaths although they won't protect in all possible cases. It would have improved adherence even without policing.