Reason that past clinical studies, focusing on health-care worker outcomes, are not the best indicator is that masks for *source-control* is not an individual level variable. It's like asking if filters on car exhausts lower air pollution by measuring the air ... inside each car.
-
This Tweet is unavailable.
-
-
Replying to @zeynep @boriquagato
Not sure why you're dismissing lab studies because measuring the filter on that exhaust is one good way to figure out what's going on. But okay, this virus is less well understood than pollution. Look at SARS is best we can do probably.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3322931/ …
1 reply 0 retweets 3 likes -
Replying to @zeynep @boriquagato
Strikingly from that study, there is a dose-response effect for the significant protection from masks. Dose-response is a pretty big signal. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3322931/ …pic.twitter.com/Zp9sfzzQ75
2 replies 0 retweets 3 likes -
This Tweet is unavailable.
-
Replying to @boriquagato
How do you randomize something you can't measure at the individual level? It's a population level outcome. But we study many things without randomization. I think lab + natural experiment papers (just starting to come out) will be the best level of evidence for this.
2 replies 0 retweets 1 like -
This Tweet is unavailable.
-
Replying to @boriquagato
There is a state mandate study (but yes confounded but at least confirms no harm/no false sense of security). https://www.healthaffairs.org/doi/10.1377/hlthaff.2020.00818 …
1 reply 0 retweets 1 like -
Replying to @zeynep @boriquagato
A few country new comparison studies are out. (I'll collect them). They all lean in the same direction, masks being protective. Again confounded but evidence keeps adding in the same direction, past source control plus lab studies showing droplets block plus natural experiments.
1 reply 0 retweets 1 like -
This Tweet is unavailable.
Will do. I'm catching up on the recent papers myself! Proper natural experiments will be the best level of evidence we have. There was talk early on doing randomized studies but people couldn't figure out any way to do it ethically or quickly.
Loading seems to be taking a while.
Twitter may be over capacity or experiencing a momentary hiccup. Try again or visit Twitter Status for more information.