[Rondec]

IMHO

" reopening " society, like " reopening " our economy, depends on the ability to get tested and get the test results quickly

without that you are playing what I have been taught to call " Russian roulette "

this type of testing needs to be done for everyone


White House, Trump among first to use Abbott rapid coronavirus tests sought by communities - The Washington Post

important governmental leaders need to be protected

an interesting side note however:



another side note

count me in on the side that would prefer to not see the president and vice president in contact with each other. I see no need for that and I see potential risks in that

The accuracy of the test is probably similar to many of the other quick tests run in a physician's office. Rapid flu swabs vary in sensitivity between 50 and 70 percent, although they are 95 percent specific. All of this means that if you have a positive test, you can be sure you have the illness, if you have a negative test you can't be sure you don't have it, and if you run them on asymptomatic people you will have a lot of false positives.

[Lowell Goudge]

I see comments like “I’m not covering my face unless it is an approved mask, or the test developer has not disclosed the accuracy.

Let’s be clear, covering your face (nose and mouth specifically) has nothing to do about keeping you safe, it is all about protecting others from you! The body of evidence is clear and growing that the biggest issue society faces is the asymptomatic contagious population. That should have been clear in early March following Rudy Gobert’s positive test on the 11th, and subsequent disclosure linking him to an infected fan on Friday the 6th in Boston, and the infection of a Detroit pistons player on the 7th. Society needs to stop the “me” attitude

As for testing, if a test can detect 75 % of the cases, that’s better than nothing, which is where we are right now. And what harm is a false positive? You isolate for 14 days, which is essentially what we are supposed to be doing now any way, along with wearing a mask to protect others from yourself.

It is time to change ME to WE

[aslyfox]

The accuracy of the test is probably similar to many of the other quick tests run in a physician's office. Rapid flu swabs vary in sensitivity between 50 and 70 percent, although they are 95 percent specific. All of this means that if you have a positive test, you can be sure you have the illness, if you have a negative test you can't be sure you don't have it, and if you run them on asymptomatic people you will have a lot of false positives.

so as a lay person

that says such tests aren't very useful

or am I misunderstanding ? [ again ]

[aslyfox]

. . . Let’s be clear, covering your face (nose and mouth specifically) has nothing to do about keeping you safe, it is all about protecting others from you! . . .

as I mentioned before

I recently heard this announcement over the radio

if you must be out and about

help your neighbor out

wear a mask

[Lowell Goudge]

The accuracy of the test is probably similar to many of the other quick tests run in a physician's office. Rapid flu swabs vary in sensitivity between 50 and 70 percent, although they are 95 percent specific. All of this means that if you have a positive test, you can be sure you have the illness, if you have a negative test you can't be sure you don't have it, and if you run them on asymptomatic people you will have a lot of false positives.

I think you have an error in your logic here.

You say if you test positive you are certain to have it, yet your last sentence is “if you runt them on asymptomatic people you will have a lot of false positives.” That’s wrong, you should say if you run them on asymptomatic people, you have a risk of missing half the infected people. But catching half is a whole lot better than none

[Serkevan]

I think you have an error in your logic here.

You say if you test positive you are certain to have it, yet your last sentence is “if you runt them on asymptomatic people you will have a lot of false positives.” That’s wrong, you should say if you run them on asymptomatic people, you have a risk of missing half the infected people. But catching half is a whole lot better than none

I think Rondec might have meant "false negatives", which would be absolutely true - and there aren't enough tests to run it triplicated to minimize errors.

---------- Post added 04-08-20 at 05:12 AM ----------

so as a lay person

that says such tests aren't very useful

or am I misunderstanding ? [ again ]

They are useful to confirm that you are sick with Covid-19 and not with something else that might be similar and require other treatment (like bacterial pneumonia, although AFAIK treatments for Covid-19 already include antibiotics to minimize the risk of opportunistic bacterial infection). A negative just means "stay staying home, it seems you weren't sick when you took the test".

[photoptimist]

building on what later proves to be a shaky foundation can cause problems as well

doesn't it ?

Sort of, yes, but ultimately, no.

The key to teaching science is to help kids (and adults) understand that science is not a set of "true facts." Instead, science is a process for testing the truth of possibilities.

What seem like "facts" in science really should be taught as "this is what we think we know so far (and why we think that), but we surely know we might be wrong."

Science really is the means for constantly testing the strength of the foundation with every new experiment and building better foundations with every new theory and hypothesis.

(Note; that's the ideal view of science is but when you add human egos and human frailties into the mix, the trajectory of science gets a lot bumpier. That leads to the joke that "science advances one funeral at a time." However, even if the weakest part of the foundation of science is humanity itself, there are parts of science that study the quirks of human senses, human cognition, human psychology, and human sociology to help us learn our own limits, watch for oft-repeated errors, and create stronger processes that transcend our weaker selves.)

[Rondec]

so as a lay person

that says such tests aren't very useful

or am I misunderstanding ? [ again ]

So, when we are talking about tests, every test has a sensitivity and specificity. Sensitivity has to do with number of false negatives versus all negatives you have and these are probably going to be higher than we would like with this test, while the specificity has to do with rates of false positive versus all positive tests and these are typically pretty good -- only in the 5 percent range. The assumption here is that the test is similar to a rapid flu test.

Pre-test probability affects the number of false positives and false negatives. If you are testing a bunch of people who do not have an illness, you are going to still get positive results, it is just that those will all be false positives. The tests look far better if you can make sure that the people you are testing have a decent chance of having the illness -- that is to say they show some symptoms or have some level of risk that increases them from the baseline.

Tests should attempt to eliminate both false positives and false negatives. As a percentage, there are typically fewer false positives than false negatives on this sort of test. But the whole point is to get information quickly and doctors still take it in advisement. "Mr. Slyfox, your rapid covid test was negative, but you still show the symptoms and so we are going to ask you to isolate for the time being and if your symptoms continue we'll run a different test..."

https://en.wikipedia.org/wiki/Sensitivity_and_specificity

[timb64]

More heartening news,thank you Cuba,both for accepting the cruise ship and the selfless act of sending 800 of your doctors abroad to assist at virus hotspots

UK thanks Cuba for ?great gesture of solidarity? in rescuing passengers from coronavirus cruise ship | The Independent

[brewmaster15]

More heartening news,thank you Cuba,both for accepting the cruise ship and the selfless act of sending 800 of your doctors abroad to assist at virus hotspots

UK thanks Cuba for ?great gesture of solidarity? in rescuing passengers from coronavirus cruise ship | The Independent

Its nice to see countries helping each others people out. Challenging times like this can bring out the best and worst in people....nice to see something positive.

Al

[Basie]

Wishing you the best of luck.

Thanks Savoche

Seems you know some of the country. That North West that I have bee visiting regularly since 1983 never gets old

[Serkevan]

More heartening news,thank you Cuba,both for accepting the cruise ship and the selfless act of sending 800 of your doctors abroad to assist at virus hotspots

UK thanks Cuba for ?great gesture of solidarity? in rescuing passengers from coronavirus cruise ship | The Independent

Cuba has a great history of humanitarian assistance, they always send help wherever needed; I personally know some Cuban people and they are all unbelievably lovely.

[Parallax]

What seem like "facts" in science really should be taught as "this is what we think we know so far (and why we think that), but we surely know we might be wrong."

Exactly!
Not too many years it was a scientific fact that there were only three states of matter.
Even fewer years ago it was still a scientific fact that nothing traveled faster than light.
Back in the very early 17th century there was a guy in Italy who got himself big trouble with the Pope for challenging the scientific fact that the sun and planets revolved around the earth.

[Serkevan]

Back in the very early 17th century there was a guy in Italy who got himself big trouble with the Pope for challenging the scientific fact that the sun and planets revolved around the earth.

Well to be fair he got himself in big trouble for challenging the biblical belief that the Sun and planets revolved around the Earth (when heliocentrism had been mathematically proven for more than a thousand years, but the Church never wanted anything to do with that because the Good Book said otherwise).

The other two are more or less kinda true, but to be fair anything that isn't one of the three "classic" states of matter gets very weird very quickly, and reality keeps functioning even if you simplify everything to solid/liquid/gas assumptions -although the difference between solid and liquid tends to depend mostly on what airport security thinks that day, which irks me after a lot of rheology studies. FTL is mostly "eeeeh", because matter still hasn't been shown to travel FTL.

It might be a good thing for some of us to go back and review the courses we took on statistics and experimental design (particularly with respect to hypothesis testing) and symbolic logic.