We don't actually know the prevalence rate because there has never been any systematic large scale teating. All asymptomatic infections are being missed. |
| You know what we don't do? Take a deliberately non-representative sample and then use this to generalize about an entire population. |
I know statistics, have taken statistics classes, conducted surveys and am an analyst. It's as good a representative sampling as one can get practically and logistically. You need to get out in the field more often. There are always trade offs that have to be made for practical reasons. |
Wow. You are not good at your job. |
You know what we do do? Fail to establish and follow through with an asymptomatic testing program in schools. Then we go on and repeat the doodoo nonsense over and over again that there is no spread in schools. |
|
https://www.washingtonpost.com/health/2021/07/27/cdc-masks-guidance-indoors/
Top health officials, who were debating the new masking guidance on Monday afternoon, said the game-changer in the discussions was new data showing that vaccinated individuals infected with the delta variant carry the same viral load as unvaccinated individuals who are infected, according to three people familiar with the data. Vaccinated people are unlikely to become severely ill, but the new data raises questions about how easily they can transmit the disease, said the three individuals. This is concerning guys. We need all the masks and testing until Less than 12s can get the vaccine. |
|
https://www.washingtonpost.com/outlook/2021/04/19/schools-covid-testing-cost/
"But there are downsides to systematic testing that have been insufficiently considered, including costs, lost learning time, logistics and stress for those subjected to such a regime. False-positive results — which say you are infected when you aren’t — pose particular problems. Overall, this kind of widespread testing fails cost-benefit analysis: It will drain already insufficient public school resources while doing little to improve safety. " "First, classrooms have thankfully been found — in studies examining schools in multiple states — to be places of limited disease transmission, compared with communities at large. The rate of transmission within schools from individuals who test positive has been estimated to be on the order of 0.5 percent to 0.7 percent (and this includes people exhibiting symptoms). A rate that low implies that a testing regimen would need to identify roughly 200 infected people to prevent one person from transmitting the disease in school. It would take an awful lot of tests to achieve those numbers. In New York City, where more than 234,000 asymptomatic students and staff members across approximately 1,600 schools were tested last fall, the overall rate of positive tests was only 0.4 percent. That suggests that — even during a time of high community spread — about 40,000 tests among asymptomatic individuals would need to be performed to prevent one in-school transmission." "And how accurate are these tests? Rapid antigen and saliva PCR tests, which are frequently used in schools, can have a false positive rate of 1 or 2 percent. That may sound low, but statisticians know that, when testing in a setting of low prevalence of disease, even a single-digit false-positive rate can be extremely problematic. The current prevalence rate for the coronavirus in the United States is roughly 15 cases per 10,000 people per week. (Prevalence in schools tends to be similar to, or lower than, that in the surrounding community.) If you give 10,000 people a test that produces false positives 2 percent of the time, that means you might get 215 positives: 15 true positives and 200 false positives. In other words, more than 90 percent of the positive test results will be incorrect." |
I'm better than you. Adapting to the unique constraints of a given situation is an important skill that you clearly do not have. |
It's going to be deliberately non-representative because you have to opt in to testing. Choice already means the sample is skewed. Next, I think you have to opt IN to testing, which means the people that don't get the forms won't bother to opt in. Given that there's a huge DCPS population that fell off the map and stopped attending any DL by the end of last year, we can assume that they are going to have a higher prevalence of not opting in. So we obviously have a unrepresentative sample. Plus evidence from last year shows that asymptomatic testing doesn't find many true positives, is prohibitively expensive when considering the spread it might prevent, and may actively do more harm than good. |
Thank you for posting this. I have read the same argument elsewhere, and it makes a lot of sense. |
Exactly. Asymptomatic testing is a waste of time. It only measures COVID; it does nothing to stop COVID once it's already in schools. That's why it's better to consider the community rate! Wastewater testing can give us this information while costing us less. |
Right. Surveillance testing would seem to make sense as part of a research study designed to compare schools v community rates. But I don't think they do much to actually prevent the spread in schools. DCPS should spend their time & energy on things that actually reduce spread and minimize disruption. |
| If "certain posts" get deleted for misinformation, can we start flagging the Covid posts that have misinformation (or at least unsupported information) for deletion? |
Why aren’t you already doing that? |
Did you see the explanation of why this isn't even a representative sample of DCPS children? The denominator here is going to be wacky. |