the latest push for masks has been as "source protection"

it's not about you, it's about being considerate & not spreading COV to others

it's a great PR soundbite and virtue signal, but is there any actual science behind it?

this study sheds real doubt https://link.springer.com/article/10.1007/BF01658736

it's a large, well designed clinical outcomes study w/ a valid control group & consistent standards.

n= 3,088.

doctors wearing face masks had 4.7% post operative wound infection rates for patients.

those with no masks had 3.5%.

wearing a mask made infection 34% more likely.

this is a stunning outcome. it's not that masks did nothing, they seem to have increased the rate of infection.

it was not quite stat sig at the P<0.05 level, but this appears to be because it was slightly under-powered. had this study been n=4000, it prob would have hit 0.05

this led me to look at this space. there is shockingly little verification in any sort of modern, outcomes based study that a doctor wearing a mask during surgery reduces infection.

you'd think this would be a slam dunk, high data, obvious outcomes issue.

it isn't.

it's a desert of absent data, dated assumptions, poor studies, and what honestly winds up looking more like superstition than science

asking doctors about it seems to be like asking villagers about the chupacabra.

everyone is sure it's there, but no one has really seen evidence

and the one really good study i could find has results in violent opposition to the standing consensus.

one good study is worth 1000 bad ones, so i tend to give it a lot of weight.

masks do not seem to work as source protection in operating theaters.

this is what makes me so suspicious of this.

if surgical and n-95 masks do not reduce (and seem to actually increase) infection rates when used by trained professionals, what hope do they have in the general population?

and viruses are MUCH harder to stop than bacteria.

lab studies do not mean anything. literally nothing.

this is the most important fact to internalize.

measuring how far a droplet travels when coughed directly through a mask 3 times is not clinically meaningful.

it's not even clinically useful.

real experience is much too complex and you cannot ever cover all the angles. maybe it does reduce cough spread. but what about mask edges? what happens after an hour of wear when the mask is wet/saturated? do you touch your face more? does virus stick more?

does the virus even really spread in droplets? is it false protection that leads you to take unsound risks? does it affect blood O2 and make you more vulnerable?

there are 1000 things going on.

testing one or 2 and saying "see it works" is nonsense.

any study not based in clinical outcomes is just myopic extrapolation by assumption.

to base policy on one is ludicrous. that's like taking a cancer drug that's only been tried in test tubes, never in vivo.

congrats, you just drank bleach.

most of the countries with less politicized covid policy advise AGAINST using masks in the general population.

all 4 nordics do. https://twitter.com/PishPishCat/status/1275710709054287872?s=20

so does US guidance and all longstanding guidance from CDC, WHO, center for evidence based medicine, and US biodefense agencies.

i discount anything they have said this year heavily.

all are being politically driven and are no longer science bodies https://twitter.com/boriquagato/status/1280990984176721920?s=20

the idea that "masks worked in asia" looks pretty iffy.

it looks a lot more like that was driven by high pre-existing immunity levels.

response (and mask use) varied widely. but none had high deaths. https://twitter.com/boriquagato/status/1280212958392446977?s=20

so, we have longstanding guidelines against masks on healthy people and even a solid study showing that masks on surgeons lead to more infections.

in the face of this, what is the case for "masks as source control"?

is there any real clinical outcomes data, even for flu?

because i have literally seen none. it's all assumptive lab test studies that measure 1 or 2 things in a contrived environment that has no resemblance to, say, a cook wearing a mask for 8 hours while making burgers.

it looks assumptive and irrelevant.

if a trained surgeon is more infective in a operating theater while wearing a mask that was fitted to them, what are the results going to be with an untrained cook over a hot stove wearing a mask they bought at costco?

hard to see them outperforming surgeons, no?

"masks are source control" just feels a little too "pat" to me.

it's too good a sound bite and too good a piece of social control propaganda to flip the assignment of responsibility and try to make it about "social consciousness' not "individual choice"

it's exactly the sort of meme that the pachinko machine of social media will spit out in 3 days of watching people make up facts and argue.

but is there any real clinical science and data behind it?

i have serious doubts.

this feels like political science, not medical.

all this said, i'm open to the idea that i missed something.

is there real clinical science here?

is there a real study, well controlled and based in clinical outcomes, (and not some parameter driven meta-study data manipulation) that shows this?