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Cognitive deficits in people who have recovered from Covid-19

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Re: Cognitive deficits in people who have recovered from Covid-19

#181
post #150

Earlier quoted context omitted.

IQ is somewhat effective as a diagnostic tool for significant impairment and not much else. Your examples of where it is not contentious are exactly cases where you must measure impairments. Do you want to list some example contexts where you witness "flat out denialism"? In any case there is an important point: The variance of measured IQ for the same individual over time is very high. It's hard to extract a signal…

> IQ is somewhat effective as a diagnostic tool for significant impairment and not much else This places exactly zero constraints on the utility of IQ tests. Instead of asking why group A scores higher than group B, I can simply ask why group B is impaired relative to group A. Apparently that should be enough to convince you of the validity of the comparison. > The variance of measured IQ for the same individual over…

Correlation being 0.8 means that R^2 is 0.64. A test that can only explain 64% of the variance in its result based on the fact that I am still me is suspect.

> This places exactly zero constraints on the utility of IQ tests. Instead of asking why group A scores higher than group B, I can simply ask why group B is impaired relative to group A. Apparently that should be enough to convince you of the validity of the comparison.

I said significant impairment. I don't mean significant in the statistical sense but in the sense of "wow that's really noticeable". Basically any test of aptitude can be used to detect lead poisoning, or the impacts of brain tumor removal, for example.

Please answer my request though, in which contexts do you think IQ suffers from denialism?

Re: Cognitive deficits in people who have recovered from Covid-19

#182

Earlier quoted context omitted.

While opinions differ on appropriate action, with some arguing for strong policy responses, there’s very little evidence of anything that merits the word “hysteria”

Really? A woman being choked in Melbourne for not wearing a mask? A man getting pepper sprayed by police at a Tim Horton's in Canada for not wearing a mask? A man getting shot in Canada, after he left the store, by police, for not wearing a mask? The Premier of Victoria locking down the entire state with tiny measures of case numbers? Continually changing news stories and narratives? The demonetization of any challen…

There are over 6 billion people on earth. This sounds like extremely isolated hysteria.

Re: Cognitive deficits in people who have recovered from Covid-19

#183
post #69

Earlier quoted context omitted.

symptoms of illness is the illness itself. Ignoring these symptoms of covid or results of the treatment is saying something like "bullets don't kill people, it ruptures blood vessels and you die due to loss of blood"

Symptoms from chemo therapy are NOT commonly classified as symptoms of the cancer that it's supposed to treat. Why do we have to make up extra rules for everything Covid-19 related?

This is a good analogy, but the conclusion I take from it is different from yours. Whether an effect of a disease is a symptom of the treatment or of the disease itself doesn't matter to me. Either way, I'd rather not get the disease if I can help it.

Re: Cognitive deficits in people who have recovered from Covid-19

#184
post #150

Earlier quoted context omitted.

> IQ is somewhat effective as a diagnostic tool for significant impairment and not much else This places exactly zero constraints on the utility of IQ tests. Instead of asking why group A scores higher than group B, I can simply ask why group B is impaired relative to group A. Apparently that should be enough to convince you of the validity of the comparison. > The variance of measured IQ for the same individual over…

Correlation being 0.8 means that R^2 is 0.64. A test that can only explain 64% of the variance in its result based on the fact that I am still me is suspect. > This places exactly zero constraints on the utility of IQ tests. Instead of asking why group A scores higher than group B, I can simply ask why group B is impaired relative to group A. Apparently that should be enough to convince you of the validity of the com…

> A test that can only explain 64% of the variance in its result based on the fact that I am still me is suspect.

The WISC full scale test correlation is 0.97, so R^2 0.94. As a reference point, you might compare to the 100m sprint [1], where the correlation is something like 0.9. If you believe that a timed run is a reliable way to determine speed, you should strongly believe an IQ test is a reliable way to determine mental ability.

> I said significant impairment

This is basically a statement about statistical power: you claim IQ is subject to large measurement error, so given typical sample sizes, we're not able to detect anything but the largest effects. But no part of this is true.

1. Good IQ proxies are reliable, i.e. they give consistent answers for a given individual.

2. Good IQ proxies are usually measurement-invariant (certainly for US samples), i.e. they measure the same thing for different groups [2]

3. Sample sizes are massive (the entire pool of SAT takers, AFQT takers, NLSY participants, etc).

> in which contexts do you think IQ suffers from denialism?

Basically all of them! You yourself just denied its validity in all but a handful of narrow situations.

[1] https://www.sciencedirect.com/science/article/abs/pii/S09608... [2] https://www.tandfonline.com/doi/full/10.1080/13854046.2016.1...

Re: Cognitive deficits in people who have recovered from Covid-19

#185
post #2

From the conclusion: "The scale of the observed deficits was not insubstantial; the 0.57 SD global composite score reduction for the hospitalised with ventilator sub-group was equivalent to the average 10-year decline in global performance between the ages of 20 to 70 within this dataset. It was larger than the mean deficit of 512 people who indicated they had previously suffered a stroke (-0.40SDs) and the 1016 who…

I’d be curious to see this compared to people hospitalized on ventilators for other diseases. You’re not in good shape at that point and I’d expect all kinds of problems.

It's not (just) a matter of whether or not Covid is worse than other serious illnesses. It's that whatever existed already, Covid adds on top of that. So if there were X people that experienced significant health problems before, now there are X + Covid.

Re: Cognitive deficits in people who have recovered from Covid-19

#186

Earlier quoted context omitted.

Please note that according to this study people who weren't critically ill still had cognitive deficits. Otherwise: Yes, other illnesses can have similar effects. Now we have another illness that piles more people on top of that. It adds to the number of people who get critically ill. It's not that Covid is worse than some other health problems, it's that Covid's impact is in addition to the ones that existed.

So COVID-19 is a special “brain wrecking” virus ?

That sounds like an extreme interpretation that would put the issue forward as a straw-man to be knocked down. Instead, I would just say that COVID is a virus that causes cognitive deficits even in people with little/no other symptoms.

Re: Cognitive deficits in people who have recovered from Covid-19

#187

Earlier quoted context omitted.

IQ tests are absolute junk as a measurement of general intelligence. IQ is a political tool not a scientific one.

Is there a better method for measuring general intelligence?

"Person, woman, man, camera, TV"?

Re: Cognitive deficits in people who have recovered from Covid-19

#188
post #94

A quick Google search reveals that cognitive deficit seems to be a common consequence in any critically ill patient, not just Covid-19 This study[1] of just one example: Cognitive dysfunction is an important long-term complication of critical illness associated with reduced quality of life, increase in healthcare costs, and institutionalization And the numbers are certainly high: Cognitive impairment was identified i…

The article specifically says that it include people that were not critically ill.

Re: Cognitive deficits in people who have recovered from Covid-19

#189
post #105
post #99

Earlier quoted context omitted.

Sure as you say critical illness with long term medical effects is known to have this impact. The difference is that, as the abstract points out, substantial cognitive impairment in Covid patients was found even in people who displayed mild symptoms and were never critically ill.

Fair point. I missed that part. Thanks. Now we should also research if viral infections in general have an association to cognitive deficit. I guess this will be the case.

The fact that your comment is still the most up voted should be part of a future psychology study where people become extremely biased towards good news when scared

Re: Cognitive deficits in people who have recovered from Covid-19

#190
post #2

From the conclusion: "The scale of the observed deficits was not insubstantial; the 0.57 SD global composite score reduction for the hospitalised with ventilator sub-group was equivalent to the average 10-year decline in global performance between the ages of 20 to 70 within this dataset. It was larger than the mean deficit of 512 people who indicated they had previously suffered a stroke (-0.40SDs) and the 1016 who…

> the hospitalised with ventilator sub-group So this affects almost nobody then, and is probably caused by the sedatives, immobilization and ventilator organ damage, aside from corona.

As many previous comments said, the article includes mild disease
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