Sweden’s approach is stupid to say the least (provided it did not take simple precautions, stated below) even disregarding the high death toll in Sweden.
One
epidemiologist acting without data is shear madness and subtle
medical dictatorship.
I need few basic data.
Is it
an enteric virus?
Is it
a respiratory virus?
Is
the mode of transmission a combination of the two?
What
is the gap period (I.C.P.) between the two?
In
other words the total incubation period assuming the enteric phase
was missed or callously disregard.
We
haven’t got the data due to lying and conniving of China and WHO.
There are a lot to blame including guys and girls in Ceylon.
Simple sanitation methods (adapted in West Africa during Ebola virus endemic) like hand washing, wearing gloves, masks and gowns are neglected world wide especially in Indian subcontinent and Africa.
Social distancing even though difficult to practice in the East (assuming respiratory mode of transmission) was outstandingly successful in the West (associated with the level of education and social responsibility).
One can be smart after the fact and the moment I got the wind of it without telling anybody, I /we kept at home for two months (wife joined) long before WHO and Ceylon recommendations.
By the time warning bells were rung, the horse had bolted from the stable.
Reproduction
Friedman:
Is Sweden getting it right with its…
President
Donald Trump has often described this pandemic as our “war” with
an “invisible enemy” — the coronavirus.
That war metaphor is
wrong and misleading.
Wars are fought and won by humans.
But when you’re in a struggle
with one of Mother Nature’s challenges — like a virus or a
climate change — the goal is not to defeat her.
No one can.
She’s
just chemistry, biology and physics.
The goal is to adapt.
Mother Nature does not reward the strongest or the smartest.
She
rewards the species that are the most adaptive in evolving the
chemistry, biology and physics that she has endowed them with to
thrive — no matter what she throws at them.
And that’s why I believe one of the most important questions we
need to answer, as these lockdowns end, is this:
Are we going to
adapt to the coronavirus —by design— the way Sweden is attempting
to do — or are we going to go the same direction as Sweden —by
messy default— or are we just going to say “the hell with
lockdowns” and go 50 different ways?
In case you’ve missed it, Sweden has taken a radically different
approach in dealing with the coronavirus. It has essentially opted
for a strategy of “herd immunity” through exposure.
This strategy posits that most people under age 65 who get the
coronavirus — if they do not have major preexisting medical
conditions — will either experience it as a typical or tough flu,
or completely asymptomatically, and the number who will get so sick
that they require hospitalization or emergency care will reliably be
less than the number of beds needed to care for them.
So, if you do your best to shelter and sequester all of those over 65
and those with serious preexisting conditions — notably heart and
lung disease and diabetes — and let much of the rest of the
population circulate and get exposed and become naturally immune,
once about 60% of your population has gone through this you’ll have
herd immunity and the viral transmission will be blocked. (This
assumes that immunity for some period of time results from exposure,
as most experts think it will.)
After all, herd immunity is our goal — either from vaccination or
from enough people building natural immunity. Those are the only ways
to achieve it.
The upside of Sweden’s strategy — if it works — is that your
economy does not take such a deep hit from lockdowns.
Anders Tegnell, chief epidemiologist at Sweden’s Public Health
Agency — the nation’s top infectious disease official and
architect of Sweden’s coronavirus response — said in an interview
published in USA Today on Tuesday: “We think that up to 25% people
in Stockholm have been exposed to coronavirus and are possibly
immune. A recent survey from one of our hospitals in Stockholm found
that 27% of staff there are immune. We could reach herd immunity in
Stockholm within a matter of weeks.”
It has come with a high cost, though. As USA Today noted: “As of
April 28, (Sweden’s) COVID-19 death toll reached 2,274, about five
times higher than in Denmark and 11 times higher than in Norway.”
Here’s the stone-cold truth: There are only different hellish ways
to adapt to a pandemic and save both lives and livelihoods. I raise
Sweden not because I think it has found the magic balance — it is
way too soon to tell — but because I think we should be debating
all the different ways and costs of acquiring immunity.
When I look across America, though, and see governors partly lifting
lockdowns — because they feel their people just can’t take it
anymore for economic or psychological reasons, even though their
populations have little or no immunity — I worry we may end up
developing more herd immunity but in a painful, deadly, costly,
uncoordinated way that still leaves room for the coronavirus to
strike hard again and overwhelm hospitals.
Herd immunity “has historically been nature’s way of ending
pandemics,” added Dr. David Katz, the public health physician who
helped kick off the debate in an essay he wrote in The New York Times
on March 20 and in a follow-up interview we did together.
“We need to bend with her forces — even when we as a species are
responsible for unleashing them,” Katz said. That means a designed
strategy, based on risk profiles, of phasing back to work those least
vulnerable, so we gradually cultivate the protection of herd immunity
— “while concentrating our health services and social services on
protecting those most vulnerable” until we can sound the all-clear.
Thomas L. Friedman is a New York Times columnist.
This
is an extremely important (and also entertaining) book that should be
mandatory reading not just for anybody interested in finding out
about what data-driven medical studies really mean, but also for
anybody engaged in any kind of empirical work. What Kendrick shows
brilliantly is the extent to which the vast majority of medical
recommendations and guidelines are based on data-driven studies that
are fundamentally flawed and often corrupt.
He
highlights how the resulting recommendations and guidelines have led
(world-wide) to millions of unnecessarily early deaths, millions of
people suffering unnecessary pain, and widespread use of drugs and
treatments that do more harm than good (example: statins), as well as
wasting billions of taxpayer dollars every year.
As
researchers who have been involved in empirical studies in a very
wide range of disciplines over many years we believe that much of
what he says is also relevant to all of these disciplines (which
include most branches of the physical, natural and environmental
sciences, computer science, the social sciences, and law).
Apart
from the cases of deliberate corruption and bias (of which Kendrick
provides many medical examples) most of the flaws boil down to a
basic misunderstanding of statistics, probability and the scientific
method.
There
are two notable quotes that Kendrick uses, which we believe sum up
most of the problems he identifies:
-
“When a man finds a conclusion agreeable, he accepts it without argument, but when he finds it disagreeable, he will bring against it all the forces of logic and reason” Thucydides.
-
“I know that most men, including those at ease with problems of the greatest complexity, can seldom accept even the simplest and most obvious truth if it be such as would oblige them to admit the falsity of conclusions which they have delighted in explaining to colleagues, which they have proudly taught to others, and which they have woven, thread by thread, into the fabric of their lives.” Leo Tolstoy
The
first sums up the extent to which results of empirical work are
doctored to suit the pre-conceived biases and hopes of those
undertaking it (a phenomenon also known as ‘confirmation bias’).
The
second sums up the extent to which there are ideas that represent the
‘accepted orthodoxy’ in most disciplines that are impossible to
challenge even when they are wrong. Those brave enough to challenge
the accepted orthodoxy risk ruining their careers in their
discipline.
Hence,
most researchers and practitioners simply accept the orthodoxy
without question and help perpetuate flawed or useless ideas in order
to get funding and progress their careers. Kendrick describes how
these problems lie at the heart of the fundamentally fraudulent peer
review system in medicine – which applies to both submitting
articles to journals and submitting research grant applications. Once
again, we believe that all of the areas of research where we have
worked (maths, computer science, forensics, law, and AI) suffer from
the same flawed peer review system.
Kendrick
is not afraid to challenge the leading figures in medicine, often
exposing examples of hypocrisy and corruption. Of special interest to
us, however, is that he also challenges the attitude of revered
figures in our own discipline. For example, Kendrick highlights two
quotes in a recent article by Nobel prize-winner Daniel Kahneman,
whose work in the psychology of decision theory and risk is held in
the highest esteem.:
-
“The way scientists try to convince people is hopeless because they present evidence, figures, tables, arguments, and so on. But that’s not how to convince people. People aren’t convinced by arguments, they don’t believe conclusions because they believe in the arguments that they read in favour of them. They’re convinced because they read or hear the conclusions from people they trust.You trust someone and you believe what they say.That’s how ideas are communicated.The arguments come later.”
-
“Why do I believe global warming is happening?The answer isn’t that I have gone through all the arguments and analyzed the evidence – because I haven’t. I believe the experts from the Academy of Sciences. We all have to rely on experts.”
Kendrick
notes the problem here:
“In
one breath he states that people aren’t convinced by arguments;
they’re convinced because they read or hear conclusions from people
they trust. Then he says that we all have to rely on experts. But he
does not link these two thoughts together to ask the obvious
question.
Just
how, exactly, did the experts come to their conclusions?”
Having
presented the BBC documentary on Climate Change by Numbers we also
got an insight into the extent to which problems exist there.
As
good as the book is (and indeed because of how good it is), we feel
the need to highlight some points where we believe Kendrick gets it
wrong.
There
are some statistical/probability errors and over-simplifications,
which mostly seem to stem from a lack of awareness of Bayesian
probability. For example, he says:
“… although
association cannot prove causation, a lack of association does
disprove causation”.
This
is not true as can be proven by the simple counter example we provide
below using a Bayesian network.
Next
we believe Kendrick’s faith in randomized
control trials (RCTs) as being the (only) reliable empirical basis
for medical decision making is misplaced. Because of Simpson’s
paradox and the impossibility of accounting for all confounding
variables there is, in principle, no solid basis for believing that
the result of any RCT is ‘correct’. As is shown in the article
here it is possible, for example, that an RCT can find a drug to be
effective compared to a placebo in every possible categorization
of trial participants, yet the addition of a single confounding
variable can result in an exact reversal of the results.
So,
if we are saying that even RCTs cannot be accepted as valid empirical
evidence, does that mean that we are even more pessimistic than
Kendrick about the possibility of any useful empirical research?
No -
and this brings us to our final major area of disagreement with
Kendrick’s thesis. In contrast to what Kendrick proposes we believe
there is an important role for expert judgment in critical
decision-making.
In
fact, we believe expert judgment
is inevitable even if every attempt is made to remove it from an
empirical study (it is, for example, impossible to remove expert
judgment from the very problem of framing the study and choosing the
variables and data to collect).
Given
the inevitability of expert judgment, we feel it should be made
obvious, transparent, and open to refutation by experiment. Any
scientist should be as open and honest about their judgment as
possible and be prepared to make predictions and be contradicted by
data.
By
combining expert judgment with data it is possible to get far more
reliable empirical results with much less data and effort than
required for an RCT. This is essentially what we proposed in our book
and which is being further developed in the EU project Bayes
Knowledge.
Refuting
the assertion “If there is no association (correlation) then there
cannot be causation”.
Consider
the two hypotheses:
-
H1: “If there is no association (correlation) then there cannot be causation”.
-
H2: “If there is causation there must be association (correlation).
Kendrick’s
assertion (H1) is, of course, equivalent to H2. We can disprove H2
with a simple counter-example using two Boolean variables a, and b,
i.e. whose states are True or False. We do this by introducing a
third, latent, unobserved Boolean variable c. Specifically we define
the relationship between a,b, and c via the following Bayesian
network :
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