3 ms·

> in a unified hospital system, a German city, a U.S. state, a panel of 15 U.S. states and Washington, D.C. as well as both Canada and the U.S. nationally. Eac

by timr 6y ago

> in a unified hospital system, a German city, a U.S. state, a panel of 15 U.S. states and Washington, D.C. as well as both Canada and the U.S. nationally. Each analysis demonstrated that, following directives from organizational and political leadership for universal masking, new infections fell significantly. Two of these studies and an additional analysis of data from 200 countries that included the U.S. also demonstrated reductions in mortality. An economic analysis using U.S. data found that, given these effects, increasing universal masking by 15% could prevent the need for lockdowns and reduce associated losses of up to $1 trillion or about 5% of gross domestic product. All of these studies were conducted on data from the spring, when cases were declining across the northern hemisphere. How are these places doing now? DC: up dramatically https://covid-19.direct/metro/DC https://covid-19.direct/metro/DC Canada: all-time highs https://www.worldometers.info/coronavirus/country/canada/ https://www.worldometers.info/coronavirus/country/canada/ Germany: all-time highs https://www.worldometers.info/coronavirus/country/germany/ https://www.worldometers.info/coronavirus/country/germany/ US nationally: all-time highs https://covid-19.direct/US https://covid-19.direct/US California: all-time highs https://covid-19.direct/state/CA https://covid-19.direct/state/CA New York: up dramatically https://covid-19.direct/state/NY https://covid-19.direct/state/NY Boston (where the "unified hospital system" was located): near all-time highs https://covid-19.direct/metro/Boston https://covid-19.direct/metro/Boston I could go on. Anyone who attempted to conduct a similar analysis today would have to credibly conclude that masks have no protective effect whatsoever. But who knows...maybe they slightly alter the slope of the curve. It's impossible to tell without a controlled trial. The german paper is particularly ironic, given that it was published approximately concurrently with a huge increase in diagnosed cases in the same city, which is now at all-time highs for the year: https://www.pnas.org/content/early/2020/12/02/2015954117 https://www.pnas.org/content/early/2020/12/02/2015954117 https://gesundheit.jena.de/en/coronavirus https://gesundheit.jena.de/en/coronavirus

PaulDavisThe1st 6y ago
> Anyone who attempted to conduct a similar analysis today would have to credibly conclude that masks have no protective effect whatsoever. Absolutely not the case. It would be just as credible, as has been noted by others in the comments here, to suggest that the major cause of spread is unmasked private gatherings. > But who knows...maybe they slightly alter the slope of the curve. It's impossible to tell without a controlled trial. I agree that without controlled trials, it is very difficult to tell definitively. That does not, however, translate into "there are lots of reasons to doubt ..."
rightbyte 6y ago
There was a empirical trail in Denmark. The difference between infection ratio and wearing a mask vs the control group was not significant. https://www.acpjournals.org/doi/10.7326/M20-6817 https://www.acpjournals.org/doi/10.7326/M20-6817 Infection with SARS-CoV-2 occurred in 42 participants recommended masks (1.8%) and 53 control participants (2.1%). The between-group difference was −0.3 percentage point (95% CI, −1.2 to 0.4 percentage point; P = 0.38) (odds ratio, 0.82 [CI, 0.54 to 1.23]; P = 0.33). Multiple imputation accounting for loss to follow-up yielded similar results. Although the difference observed was not statistically significant, the 95% CIs are compatible with a 46% reduction to a 23% increase in infection.

by timr 6y ago

PaulDavisThe1st 6y ago

> Anyone who attempted to conduct a similar analysis today would have to credibly conclude that masks have no protective effect whatsoever. Absolutely not the case. It would be just as credible, as has been noted by others in the comments here, to suggest that the major cause of spread is unmasked private gatherings. > But who knows...maybe they slightly alter the slope of the curve. It's impossible to tell without a controlled trial. I agree that without controlled trials, it is very difficult to tell definitively. That does not, however, translate into "there are lots of reasons to doubt ..."

rightbyte 6y ago

There was a empirical trail in Denmark. The difference between infection ratio and wearing a mask vs the control group was not significant. https://www.acpjournals.org/doi/10.7326/M20-6817 https://www.acpjournals.org/doi/10.7326/M20-6817 Infection with SARS-CoV-2 occurred in 42 participants recommended masks (1.8%) and 53 control participants (2.1%). The between-group difference was −0.3 percentage point (95% CI, −1.2 to 0.4 percentage point; P = 0.38) (odds ratio, 0.82 [CI, 0.54 to 1.23]; P = 0.33). Multiple imputation accounting for loss to follow-up yielded similar results. Although the difference observed was not statistically significant, the 95% CIs are compatible with a 46% reduction to a 23% increase in infection.