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Post by bernythedolt on Oct 16, 2020 12:38:42 GMT
I'd urge you to read the following twitter thread... An easier to read version is available here... threadreaderapp.com/thread/1316511734115385344.htmlIt contains fundamental flaws and biases, for example: and it uses so-called convenience samples to estimate seroprevalence. Convenience samples are those gathered at the same time as the primary blood letting, e.g. those who donate blood. It doesn't take an epidemiologist to know that those willing to give blood during a pandemic are more likely to have been infected (it's also supported by the data). Edit: I'd also urge you to read this review of IFR... www.sciencedirect.com/science/article/pii/S1201971220321809All good points - I am certainly not advocating Ioannidis as "right", only suggesting that there is a range of views, the evidence base is arguable and dynamic, and that as ever the tendency in this pandemic is to angrily vent against anyone who expresses a different view as to the nature of the virus and what to do about it all. The main thing for me is that there *isn't* an IFR, there is only an IFR by population and time. But people are now arguing as to whether it is (on average) 0.3 or 0.6% essentially. Look back several hundred pages of this thread and recall people were suggesting rates an order of magnitude higher, which I never thought was likely (albeit that my argument logically suggests that the IFR may well have been higher back then due to the ages/vulnerabilities affected, and time i.e. lack of knowledge and treatment). Whilst acknowledging you've always felt the IFR (infection fatality ratio) would likely be well below 1%, much of the previous discussion has centred on CFR (case fatality ratio) and we should be careful not to elide the two. Even Ioannadis's controversial March paper talked about his CFR estimate of 0.3%. He didn't mention IFR back then (because it's largely guesswork). Large swathes, indeed most of the world (see Johns Hopkins, under CFR tab), still has a CFR of 5% to 15% today, including the UK. Mexico is around 17% in places. This is the thick end of a year into the pandemic, so I think we can reasonably say Ioannadis's estimate for CFR of 0.3% was out by an order of magnitude. CFR is defined as the proportion of deaths to cases. Taken globally, Worldometers shows 1.104m deaths from 30.527m cases, and a CFR of 3.6% (which they round to 4%). After nearly a year. And CFR is really the only metric we can state with some degree of certainty, which is why Johns Hopkins and Worldometers quote it and pandemics are recorded on the historical record with it. CFR is real, tangible and countable as opposed to IFR which is more of an academic measure.
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benaj
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Post by benaj on Oct 16, 2020 12:46:28 GMT
All good points - I am certainly not advocating Ioannidis as "right", only suggesting that there is a range of views, the evidence base is arguable and dynamic, and that as ever the tendency in this pandemic is to angrily vent against anyone who expresses a different view as to the nature of the virus and what to do about it all. The main thing for me is that there *isn't* an IFR, there is only an IFR by population and time. But people are now arguing as to whether it is (on average) 0.3 or 0.6% essentially. Look back several hundred pages of this thread and recall people were suggesting rates an order of magnitude higher, which I never thought was likely (albeit that my argument logically suggests that the IFR may well have been higher back then due to the ages/vulnerabilities affected, and time i.e. lack of knowledge and treatment). Whilst acknowledging you've always felt the IFR (infection fatality ratio) would likely be well below 1%, much of the previous discussion has centred on CFR (case fatality ratio) and we should be careful not to elide the two. Even Ioannadis's controversial March paper talked about his CFR estimate of 0.3%. He didn't mention IFR back then (because it's largely guesswork). Large swathes, indeed most of the world (see Johns Hopkins, under CFR tab), still has a CFR of 5% to 15% today, including the UK. Mexico is around 17% in places. This is the thick end of a year into the pandemic, so I think we can reasonably say Ioannadis's estimate for CFR of 0.3% was out by an order of magnitude. CFR is defined as the proportion of deaths to cases. Taken globally, Worldometers shows 1.104m deaths from 30.527m cases, and a CFR of 3.6% (which they round to 4%). After nearly a year. And CFR is really the only metric we can state with some degree of certainty, which is why Johns Hopkins and Worldometers quote it and pandemics are recorded on the historical record with it. CFR is real, tangible and countable as opposed to IFR which is more of an academic measure. I have started to wonder why this government is so keen on testing and found more positive cases. Could it be massaging the stats in order to keep CFR below 15% today? The CFR in the UK was probably the highest around 15% until now. Mexico has managed to come on top in the CFR league table.
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registerme
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Post by registerme on Oct 16, 2020 12:49:42 GMT
Re the CFR / IFR discussion, I, for instance, almost certainly had COVID-19, but I did not get tested. That puts me in the IFR bucket. Simply by getting tested I would change the CFR number.
I agree that CFR is the more clearly quantifiable of the two measures, but both measures have their deficiencies.
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mrk
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Post by mrk on Oct 16, 2020 18:11:21 GMT
I agree that there isn't a single IFR and that it varies by population and time. My starting point for my own investigations were the criticism of Ferguson et al estimate of 0.9% as it was, stratified across the UK age demographic - the evidence simply does not support that criticism. Someone mentioned Bangladesh yesterday, where you would expect a much lower IFR simply because of the age demographic (even accounting for their poorer healthcare system), but that doesn't have a bearing on the IFR in the UK. We're also going to see IFR trending lower as treatments improve mortality rates but it doesn't invalidate the findings of Ferguson et al. For the same reasons I also object to Ferguson being vilified as has also occurred. Ferguson's model in March predicted 250,000 deaths in the UK in a "mitigation" scenario where most of the population would be infected in a single wave. The UK has so far recorded over 43,000 deaths (57,000 if you look at death certificates) with maybe 15% of the population infected, so those estimates don't look far off from reality. Seems to me those who argue that far less people have died than predicted are simply not taking into account what percentage of the population has been infected so far.
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benaj
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Post by benaj on Oct 17, 2020 17:35:52 GMT
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Post by dan1 on Oct 18, 2020 9:24:03 GMT
The scientific groundwork has been laid for a two week "circuit-break" framed as reducing deaths by between 29% and 49% by the end of the year... www.bmj.com/content/371/bmj.m4038I'm not advocating for such but hadn't seen it published (well, as a preprint) until now. I was made aware by a tweet from the most well-known German scientist* on Covid-19, Christian Drosten. I kind of like the Welsh term for this as a "fire-break" - acknowledges that we're currently on-fire! * on reflection, that is surely Angela Merkel!
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benaj
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Post by benaj on Oct 18, 2020 9:33:24 GMT
The scientific groundwork has been laid for a two week "circuit-break" framed as reducing deaths by between 29% and 49% by the end of the year... www.bmj.com/content/371/bmj.m4038I'm not advocating for such but hadn't seen it published (well, as a preprint) until now. I was made aware by a tween frm the most well-known German scientist on Covid-19, Christian Drosten. I kind of like the Welsh term for this as a "fire-break" - acknowledges that we're currently on-fire! The "two week circuit breaker" was said on 21st Sept right? We are on the path heading hard Winter. While other countries like Germany and Italy have acted quickly below reaching 100 daily deaths , at the current rate, the UK will overtake Russia very soon in daily COVID death.
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agent69
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Post by agent69 on Oct 18, 2020 11:20:51 GMT
The scientific groundwork has been laid for a two week "circuit-break" framed as reducing deaths by between 29% and 49% by the end of the year... www.bmj.com/content/371/bmj.m4038I'm not advocating for such but hadn't seen it published (well, as a preprint) until now. I was made aware by a tween frm the most well-known German scientist on Covid-19, Christian Drosten. I kind of like the Welsh term for this as a "fire-break" - acknowledges that we're currently on-fire! The "two week circuit breaker" was said on 21st Sept right? We are on the path heading hard Winter. While other countries like Germany and Italy have acted quickly below reaching 100 daily deaths , at the current rate, the UK will overtake Russia very soon in daily COVID death. Only if you are naive enough to believe the Russian figures.
All of Europe is struggling with a second wave, and the infection rate in Italy has quadrupuled in two weeks (corresponding increase in death rate to follow shortly?). I don't believe that any country has implemented a short circuit breaker type lock down, and I can't see it being effective. The original lockdown started late March when cases were 1000 a day. With everything closed except supermarkets and chemists, the rate increased to 3000 during April and it was not until late May (2 months into lockdown) that the infection rate got down to where it was when lockdown started.
It will be enteresting to see how the short term lock down affects rates in NI (and Wales if implemented), but I can only see it as a sticking plaster which isn't going to solve the wider problem. Bottom line is we are stuck with this virus until:
- people learn to follow the rules
- somebody developes an effective vacine
- sufficient people contract the virus for herd immunity to work
- the virus mutates into something we can live with
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benaj
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Post by benaj on Oct 19, 2020 14:29:13 GMT
Data from Week 41, suggests shopping might not be COVID secure as we thought
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registerme
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Post by registerme on Oct 19, 2020 14:37:30 GMT
I'm not sure data like that is very helpful. Pulling numbers out of thin air let's say that 40 million people a week go to a supermarket at least once a week, and 200 thousand work in a warehouse.
Of the common locations, was it evenly distributed across all supermarkets, but concentrated on two warehouses? Of the "in the home" infections, how many were "own home" and how many were "staying somewhere else?
etc etc etc etc
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benaj
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Post by benaj on Oct 19, 2020 14:39:16 GMT
True, it would be more useful the app warns us about the common locations that we are visiting.
Yet, not many headlines about supermarket being shutdown due to COVID outbreak or being traced as common location. Business as usual for them.
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Post by Ton βββ on Oct 19, 2020 17:44:11 GMT
I'm not sure data like that is very helpful. Pulling numbers out of thin air let's say that 40 million people a week go to a supermarket at least once a week, and 200 thousand work in a warehouse. Of the common locations, was it evenly distributed across all supermarkets, but concentrated on two warehouses? Of the "in the home" infections, how many were "own home" and how many were "staying somewhere else? etc etc etc etc
With a massive jump in online grocery shopping they (PHE?) must be able to do an analysis to see if one of these groups has a degree of protection and the other not
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registerme
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Post by registerme on Oct 19, 2020 18:06:44 GMT
Great, I get to have a second crack at this (it's like a free bet from Paddy Power!). My builder was round this afternoon to have a look at a water leak coming in from the roof somewhere (likely my solar PV ). His son works for McLaren Racing, and they test their staff every second week - he tested positive this evening. This year just keeps on giving and giving .
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Post by dan1 on Oct 19, 2020 19:27:37 GMT
I'm not sure data like that is very helpful. Pulling numbers out of thin air let's say that 40 million people a week go to a supermarket at least once a week, and 200 thousand work in a warehouse. Of the common locations, was it evenly distributed across all supermarkets, but concentrated on two warehouses? Of the "in the home" infections, how many were "own home" and how many were "staying somewhere else? etc etc etc etc
With a massive jump in online grocery shopping they (PHE?) must be able to do an analysis to see if one of these groups has a degree of protection and the other not
I hope PHE/Test & Trace are sharing anonymised data to allow researchers to do this kind of analysis. I have some doubts that they actually have the fidelity of data required to perform these analyses because we'd of already seen the findings. Does the new Apple/Google decentralised app prevent collection of this data, I don't know? I'd bet my P2P assets ( ) that the online shoppers have a statistically significant lower rate of infection than those doing in-person grocery shopping. But, that tells us little I suspect. Those daily supermarket shoppers are more likely to go to restaurants, cafes, pubs, jet off on holiday. I guess what I'm trying to say that isolating one variable amongst all the other interactions must be pretty damn hard statistically. Perhaps there should be more stats taught at school given the recent battlegrounds - climate change, brexit economics, Covid-19?
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registerme
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Post by registerme on Oct 19, 2020 19:59:54 GMT
Those daily supermarket shoppers are more likely to go to restaurants, cafes, pubs, jet off on holiday. They are? Sounds like a bit of an assumption to me.
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