Numbers don’t lie. Masks work.

[Cosmic Wonder]

www.npr.org/sections/health-shots/2020/11/23/937173060/mask-mandates-work-to-slow-spread-of-coronavirus-kansas-study-finds

Mike

[coachdoc]

Yup.

[Village Idiot]

Not going to argue that one.

[james]

An angry and tired nurse vents on Twitter.

threadreaderapp.com/thread/1330328485265612804.html

[xyrn]

I'm angry and tired, too.
Here's a bit of what I was discussing with some friends about my local perspective:

I can't hunker down, but hanging in there. Our ICU is over 25% COVID and we've had all beds filled for weeks. The COVID pts we're getting are sicker than the ones we had a week or two ago. Over a hundred in isolation throughout the hospital for confirmed and or suspected cases. Having a covid death in my 23 bed icu about every other day now. Vents and bipaps sometimes in full use with zero available for hours at a time (until someone dies or gets a bit better and doesn't need it). 5 of our icu staff of 120 currently have covid.
Running out of the paralytic drugs and the inhaled nebulizer solution that we bleed into the vent circuits on really sick patients. Running out of certain n95 masks so being re fit tested for construction grade n95s.
But other than that, everything is just fine.

I've been wearing my privately purchased faceshield since March, and my own goggles since July - and now that we're being issued lesser grade N95s I've started wearing my privately purchased P100 cartridge respirator, that is NOT authorized by my facility, into COVID rooms.

So far nobody has talked to me about it, not sure what I'll do if mgmt gives me pushback...

[james]

Snappy duds Kris! 😯 I was wondering how you were bearing up. Courage mon brave!

[billhammond]

Thanks for the update, Kris -- you guys are so amazing under duress.

[TKennedy]

Proud of you Kris. You own that outfit.

[coachdoc]

Kris, you are the very definition of a front line hero. Thank you.

[Village Idiot]

That's great, Kris! If you're running out of masks, I'm sure they're not planning on arguing with you on what you've got. Good for you. And hang in here. Many people need your help, and you're giving it to them.

[epaul]

Nov 24, 2020 0:17:21 GMT -5 xyrn said:

Say, that outfit will come in handy when you decide to re-finish all your guitars and give them sunbursts!

[fauxmaha]

I must be bored this morning. I started reading the study, and this popped out at me:




0.25 vs 0.08? Something's up with that.

So I went looking in the study for an explanation, and they don't have one. Unless someone can explain to me what I've got wrong here, I think the study is (really, ridiculously) flawed.

Every epidemic/pandemic/whatever follows more or less the same path. No cases, then cases jump up, then the epidemic burn itself out and it tails back off. The slopes going up and coming down can vary depending on the particulars of the epidemic, but more or less they always look like this:



When those charts are created, the question that always comes first is "On what date did the epidemic start?" Epidemiologists generally use "the date of the 1000th case" to define that moment. There isn't anything magic about the number 1000. You can use 10, or 100, or 10,000 or whatever. The point is you need a normalized metric for defining the start of an epidemic in a given population.



The reason for that is that different populations will all, more or less, experience the same epidemic curve. It will go up, and it will go down, and it will follow the same general shape. But, depending on the date a given population is "seeded", the curves will start at different times:



For reasons that are both self-evident and made abundantly clear by our experience with epidemics, higher population/higher density locations tend to start on the curve sooner than lower population/lower density locations. There's a reason that the first heavy outbreak of Covid in the US happened in New York and not Cherry County, Nebraska.

The fatal flaw in the Kansas study is that they made no effort to account for that basic epidemiological fact. 

Kansas implemented a mask mandate, but there was spottiness across counties on its implementation. Some opted out. The counties with a mandate were the higher population/higher density ones, and the counties without a mandate were the lower population/lower density ones. What the study was looking at was something like this:



So "Someplace" (ie, the larger, higher density counties) experienced this:



And "Someplace Else" (the smaller, lower density counties) experienced this:



All of which is to say: The study claims to be measuring the effectiveness of mask mandates, but I say all they are measuring is the fact that the epidemic hit sooner in bigger counties than smaller counties.

All that is theoretical. Here are some actual county-level charts. First, Douglas county, a relatively high population county:



Here is Logan county, a small population county:



If you superimpose one on top of the other, you see that it reflects exactly what I was speculating: The epidemic hit Douglas well before it hit Logan.

(The vertical axis becomes meaningless when you do this, but the shape of the curves still has information.)



Go back to that quote I started with. What does 0.25 vs 0.08 mean? What it means, and I think the subsequent analysis I've presented here bears it out, is that all this study really shows is the effect of different epidemic start dates in different locations.

This final graph is also noteworthy. It shows is that the "mask mandate" counties are gaining new cases at a higher rate than "no mask mandate" counties. The fact that the mask mandate counties are seeing a downward trend in new cases, and the no mask mandate counties are seeing an upward trend is further evidence that all this study really does is look indirectly at epidemic start dates.



Nothing in my analysis should be taken as "I just proved masks don't work". But nothing in this study supports the conclusion that masks work. 

[epaul]

The Kansas mask requirement went into effect on July 3, when coronavirus cases were rising across the state. But 81 counties opted out of the mandate, as permitted by state law. The other 24 counties — which account for the majority of the state's population — chose to require that masks be worn in public places.

You appear to have a good point, Jeff. The paragraph above by itself indicates a urban/rural split in the study that could reasonably affect the results of the study. There are evidentiary reasons that can account for why an epidemic curve would get kicked into gear earlier in a densely populated urban center (along its airports, hospitality centers, universities, and hospitals) than in sparsely populated (by comparison) rural areas (that also have a lessened exposure to the "outside"... no airports, hospitality centers, business/school travel etc.).

I recall a study done in Minnesota a good while back that demonstrated that people who lived in rural/agricultural counties experienced higher rate of various cancers on a per capita basis than people who lived in the urban centers of the state. The study got a lot of coverage and generated a lot of commentary on farming practices. Later, the study came under criticism for not taking the median age of the rural and urban areas studied. Turned out the median age of the urban residents studied was nearly eight years younger than the age of the rural residents... and all the study demonstrated was that a population of older people will have an higher incidence of cancer than a population of younger people.

As you said, it appears there may be an issue with the study that merits comment. And, as you said, it is a comment on the study itself, not a comment on the general body of work and experience that informs what is currently understood about masks and disease transmission.

[John B]

Jeff,

I would have a better understanding of your post if you used Papyrus for your graphs.

[coachdoc]

Not relevant.
Amount of exposure and virulence of the infecting particles not taken into account. If you are hit with larger doses more frequently you will get the illness more frequently. If you wear a mask you reduce the number and amount of exposures and get less frequent illnesses. Not none, just less. It is insane not to wear a mask if you don't want to get ill with Covid.

[Deleted]

Does anyone on the forum really have the depth of knowledge, education, experience and multi-disciplinary expertise required to credibly dispute a study compiled and authored by five PhDs and three MPHs? Is there any evidence the authors abandoned academic rigor or ignored professional standards?

I have my doubts.

This isn't like amateur backyard astronomers discovering an asteroid. This is an issue that combines several specialized scientific disciplines. I'm inclined to believe them, for now.

[epaul]

Whatever curiosity may have made you a good reporter appears to be long gone.

[millring]

as rude and unfriendly as anything Peter ever posted. Personal attacks aren't made palatable by style.

[John B]

Nov 24, 2020 19:16:55 GMT -5 millring said:

as rude and unfriendly as anything Peter ever posted. Personal attacks aren't made palatable by style.

I'm inclined to give Paul the benefit of the doubt on this one.

[theevan]

I'm safe because I have no earthly idea what fauxmaha is talking about.

I like the squiggly lines.