Biostatistics Professor Jon Deeks has written a critical piece on the shortfalls of the current mass testing regime for children in schools. Of particular concern is the occurrence of false positives. UnHerd has the story.
The fitness for purpose [of the testing regime] is a combination of the sensitivity of the test (what percentage of infected cases it correctly identifies) and the specificity (what percentage of uninfected people it correctly says are negative). But it also depends on how, where and when a test is used.
Different studies of the UK Innova lateral flow test (the test being used in schools) have reported variously that its sensitivity is 78%, 58%, 40% and even 3%. The higher 78% and 58% figures come from using the test among people with symptoms, the lower 40% and 3% figures come from using it for mass testing among people without symptoms, as is being done in schools. (And none of these studies have assessed how well the test detects infection in children). So although the test can pick up people who have the infection, it will miss quite a few – so there is a risk that disinhibition after a negative test could actually exacerbate case numbers if children incorrectly think they are safe and the rules no longer apply.
But the more concerning aspect are the false positives, related to the specificity. The original Government studies found only around 3 in 1,000 people were getting false positives, and this dropped to 1 in 1,000 in the Liverpool study. Doesn’t sound like a lot, right?
But consider the problem from the perspective of a pupil who has just got a positive test result. The reasonable question for them (and their parents) to ask is “what are the chances that this is a false positive?” Given that a positive test result means the pupil, their family and their school bubble will have to isolate for 10 days, a high false positive probability is a real problem.
Jon, who is a Senior Researcher in the Institute of Applied Health Research at Birmingham University, goes on to outline three scenarios regarding the prevalence of the disease and the accuracy of the tests.
Where 1 in 100 pupils have the infection (Scenario A), by testing a million we would find 5,000 cases but get 990 false positives. This ratio of true to false positives is quite favourable – 5 out of every 6 with positive results actually would have COVID-19 infection – so the probability that the pupil genuinely has the infection is over 80%.
However, the picture becomes less favourable as the infection becomes rarer: if only 1 in 1,000 pupils were infected (Scenario B) we would detect 500 cases but get 999 false positives. The ratio of true to false positives is now unfavourable – one true result for every two false results.
If only 1 in 10,000 had the infection there would be one true result for every 20 false results (Scenario C). Why would anybody consent to a test where the chances that a positive result is wrong are so much higher than it is right? This isn’t the fault of the test – it’s the application in a low prevalence setting. Using any test – even one with an incredibly high specificity – will lead to more false than true positive results when the disease becomes rare.
Worth reading in full.
Stop Press: The Government’s refusal to let pupils use follow-up tests to confirm positive Covid results is “ruining” their return to school, parents say.
Stop Press 2: Professor Deeks made the same point in an interview for Radio 5 Live.
— BBC Radio 5 Live (@bbc5live) March 11, 2021
"Most of the positive results we’re seeing at the moment are probably false positives and not true positives"
@deeksj Professor of Biostatistics tells @rachelburden that using lateral flow tests won't make schools completely safehttps://t.co/JGGyzav25c
@BBCSounds pic.twitter.com/DbfEme8lYn
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Viruses do what viruses do.
They exist to exist!
Why would a piece of RNA inside a capsid do any of ths?
The key point remains that SARS-Cov-2 does not warrant any exceptional measures, anyway. Let’s not forget the fundamental con.
I can’t remember exactly where, so don’t have a link, but there was a peer-reviewed study posted a long time back that concluded the same, that there was no correlation between lockdowns and mortality, except in geographically isolated countries that could shut their borders *before* the virus arrived, NZ being the obvious example. This would make sense: if you have a very low incidence, then localised lockdowns can nip the breakouts in the bud, so to speak. But once the virus is endemic, good luck with that.
BTW: I think NZ is a s**tfest for other reasons.
We have family in New Zealand, including our only grandchild who is three and a half, that we haven’t seen since January 2020.
Closing borders like New Zealand has was and could only ever have been a temporary measure. The virus has embedded itself as a worldwide endemic disease ad now NZ has to go through what we have been through to achieve any sort of natural resistance.
In the meantime its economy, fsmily life’ health and particularly mental health all suffer.
I’m in NZ and matters are grim here in my view. People who are still asleep may disagree. At best IMO all that our draconian lockdowns and border closures have done is delay the inevitable. We are at the beginning of our first real wave but still in an effective lockdown, with “vaccine” passports, loads of “vaccine” mandates leaving sectors that were already under pressure like Health and Education scrambling for staff, nearly everyone wears a mask everywhere (we have mask mandates for most things). Mental health, which was strained before Covid seems terrible. People seem angry and scared (either of Covid, or of the State). Businesses are going under at unheard of rates. Our healthcare system is very strained. We have tens of thousands of kiwis who can’t get home because of the border controls. Whilst the wave we are in seems to be declining, probably because of summer and a freshly jabbed population, when the jabs wear off in time for the winter I suspect we will see a massive outbreak.
My partner/girlfriend has just told me that at the church in the next town northwards (it’s the town this village is joined to) there’s a Christmas Carols thingy coming up – but – you guessed it – only for the ‘vaccinated’. The ‘unvaccinated’ are NOT welcome. My partner is ‘vaccinated’ (double jabbed) and could go but says she’s not, out of principle.
It’s quite disgusting how these ‘Christians’ are tending to their flocks. Why don’t the vicars and bishops just cart the ‘unvaccinated’ off to the gas chambers and get rid of the lot?
This is in Finland, where the ‘News on the television keeps bleating out “Corona passes” “Corona Passes” “Corona Passes” “cases!” “cases!” “cases!”…
It’s “THE LOVE OF”
sorry this thing get me annoyed.
Money is just an aid to temporal barter, i.e you can get things when you need them, not just when you have something to exchange (as in normal barter). i.e. you can store you time*productivity until you actually need someone else’s time.
https://en.wikipedia.org/wiki/Jesus_cleansing_a_leper
Just protest outside by reading all three of the Synoptic Gospels: Matthew 8:1–4, Mark 1:40–45 and Luke 5:12–16.
And maybe wear some sort of yellow badge – perhaps one with “ungeimpft” on?
Given that the covid mortality figures are a palpably fraudulent fantasy, then yes, I’d say that was a weakness.
A lot of the counter-analysis floating around suffers from the same problem: accepting, as a core premise, some aspect of the official narrative. What surprises me is that, after two years of lies, otherwise critical thinkers still mount arguments that fail to trace back assumptions to the root.
I would suggest that readers track back to the original papers, or direct analysis thereof, that claimed the existence of a new virus in the first place. It’s full of holes you could drive several coaches through. It’s barely credible.
The Corman-Drosten paper that managed to deliver a ‘test’ for the elusive new virus, without having a sample of supposed virus to work on? Methodically questionable, to say the least. And that’s before we get to the blatant conflicts of interest, or the 24-hour peer review. This too is not a credible piece of work.
Dr Andrew Kaufman has given Sayer Ji (find it on Odysee) a review of the (absence of) ‘science’ underpinning the new variant. You owe it to yourselves to check it out.
This crap will continue until more people get over their last vestiges of cognitive dissonance, and take a sober look at the first principles, the root narrative. After all, if many now accept that their governments and establishment institutions have engaged in a 2-year campaign of fraud and lies, it seems appropriate to go ‘full red pill’ and reassess the starting point for all this.
The holy of holies for those promulgating this barrage of bullshit is that the core narrative must be believed. The house of cards rests on that. In our vestigial faith that, somehow, our institutions can’t be that cynical, we are complicit in the cover-up. It’s like a disappointment too far: the final realisation that much of what you experience in life is someone else’s narrative. But blow down the house of cards, and you can begin to think more clearly.
Are the dates correct on those charts?
Noah
Another great analysis. Why on Earth do other journalists, government scientists and politicians not do this work, or at least pick it up and repeat it or discuss it?