...So, to this article. Its about the testing we do with something called PCR, an amplification technique, better known to biologists as a research tool used in our labs, when trying to unpick mechanisms of disease. I was frankly astonished to realise they’re sometimes used in population screening for diseases – astonished because it is a very exacting technique, prone to invisible errors and it’s quite a tall order to get reliable information out of it, especially because of the prodigious amounts of amplification involved in attempting to pick up a strand of viral genetic code. The test cannot distinguish between a living virus and a short strand of RNA from a virus which broke into pieces weeks or months ago.
I believe I have identified a serious, really a fatal flaw in the PCR test used in what is called by the UK Government the Pillar 2 screening – that is, testing many people out in their communities. I’m going to go through this with care and in detail because I’m a scientist and dislike where this investigation takes me. I’m not particularly political and my preference is for competent, honest administration over the actual policies chosen.
... The bottom line is that it is reasonable to expect the prevalence of the virus to be close to the number found by ONS, because they sample randomly, and would pick up symptomatic and asymptomatic people in proportion to their presence in the community. As of the most recent ONS survey, to a first approximation, the virus was found in 1 in every 1000 people. This can also be written as 0.1%. So when all these 10,000 people are tested in Pillar 2, you’d expect 10 true positives to be found (false negatives can be an issue when the virus is very common, but in this community setting, it is statistically unimportant and so I have chosen to ignore it, better to focus only on false positives).
So, what is the false positive rate of testing in Pillar 2? For months, this has been a concern. It appears that it isn’t known, even though as I’ve mentioned, you absolutely need to know it in order to work out whether the diagnostic test has any value! What do we know about the false positive rate? Well, we do know that the Government’s own scientists were very concerned about it, and a report on this problem was sent to SAGE dated June 3rd 2020. I quote: “Unless we understand the operational false positive rate of the UK’s RT-PCR testing system, we risk over-estimating the COVID-19 incidence, the demand on track and trace and the extent of asymptomatic infection”. In that same report, the authors helpfully listed the lowest to highest false positive rate of dozens of tests using the same technology. The lowest value for false positive rate was 0.8%.
Allow me to explain the impact of a false positive rate of 0.8% on Pillar 2. We return to our 10,000 people who’ve volunteered to get tested, and the expected ten with virus (0.1% prevalence or 1:1000) have been identified by the PCR test. But now we’ve to calculate how many false positives are to accompanying them. The shocking answer is 80. 80 is 0.8% of 10,000. That’s how many false positives you’d get every time you were to use a Pillar 2 test on a group of that size.
The effect of this is, in this example, where 10,000 people have been tested in Pillar 2, could be summarised in a headline like this: “90 new cases were identified today” (10 real positive cases and 80 false positives). But we know this is wildly incorrect. Unknown to the poor technician, there were in this example, only 10 real cases. 80 did not even have a piece of viral RNA in their sample. They are really false positives.
I’m going to explain how bad this is another way, back to diagnostics. If you’d submitted to a test and it was positive, you’d expect the doctor to tell you that you had a disease, whatever it was testing for. Usually, though, they’ll answer a slightly different question: “If the patient is positive in this test, what is the probability they have the disease?” Typically, for a good diagnostic test, the doctor will be able to say something like 95% and you and they can live with that. You might take a different, confirmatory test, if the result was very serious, like cancer. But in our Pillar 2 example, what is the probability a person testing positive in Pillar 2 actually has COVID-19? The awful answer is 11% (10 divided by 80 + 10). The test exaggerates the number of covid-19 cases by almost ten-fold (90 divided by 10). Scared yet? That daily picture they show you, with the ‘cases’ climbing up on the right-hand side? Its horribly exaggerated. Its not a mistake, as I shall show.
... This test is fatally flawed and MUST immediately be withdrawn and never used again in this setting unless shown to be fixed. The examples I gave are very close to what is actually happening every day as you read this...
https://lockdownsceptics.org/lies-da...lse-positives/
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Originally Posted by wacojoe
