this post was submitted on 29 Aug 2025
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[–] echolalia@lemmy.ml 5 points 1 day ago (2 children)

Don't you think calling a proportional hazards model "guessing" is doing a disservice to Lemmy posters here? Not everyone has a background in statistics, and honestly quite a few people here struggle with highschool math. It's not much different than linear regression. Its fancy linear regression, not fancy guessing.

Does their model not fit or something?

[–] jet@hackertalks.com 2 points 1 day ago* (last edited 1 day ago) (1 children)

At its most essential level - when you have a epidemiology dataset you don't know the relationships until you analyze the data, in order to make controls for some factors in the data you have to assume some relationship for that factor. It's typically assumed to be some linear relationship. If you knew the relationship between factors with certainty, you wouldn't need a epidemiological dataset in the first place, but since we are trying to control for a confounder by definition we don't know the relationship. It is a guess in colloquial terms, a educated guess to be sure, but still a guess.

This is a good overview of cause and effect in inferential statistics, and confounders (start at the 5 minute mark) https://www.youtube.com/watch?v=n4YV7tEtg3I

If you prefer something written with more rigor: https://pmc.ncbi.nlm.nih.gov/articles/PMC4017459/

the researchers should notice that wrong assumptions about the form of the relationship between confounder and disease can lead to wrong conclusions about exposure effects too.

This is a critical weakness of epidemiology when inferences are made about something not directly measured.

[–] echolalia@lemmy.ml 6 points 1 day ago (1 children)

while all true, I'm taking issue with you calling it guessing, not that it's a perfect method.

also, we use epidemiological data because it's kind of hard to do a double blind study where you tell some group of people to eat meat for 20 years, and another group of people to not eat meat for 20 years, and then have them live exactly identical lives for that 20 years.

you're kind of not mentioning that. it's kind of dishonest when the audience (Lemmy) is full of layman who are definitely not reading your linked citations, I certainly don't have time to. I'm not defending this study at all because I haven't read it, I'm just taking issue with how you are presenting these (useful) techniques

[–] jet@hackertalks.com 1 points 1 day ago (2 children)

These are useful techniques to generate hypothesis to test, absolutely!

The results from epidemiology, especially weak hazard ratios, and poor confounders, really have no business being publicized to lay people to get them to change any aspect of their life.

also, we use epidemiological data because it’s kind of hard to do a double blind study where you tell some group of people to eat meat for 20 years, and another group of people to not eat meat for 20 years, and then have them live exactly identical lives for that 20 years.

Sure, but that isn't science. Science is a falsifiable hypothesis that can be tested, if we say we can't test these things then we are not in the realm of empiricism but of theology. That is fine, but we should be clear that the message isn't backed by science.

[–] echolalia@lemmy.ml 5 points 1 day ago (1 children)

Good lord there should be a confirmation for the delete button.

Anyway,

The results from epidemiology, especially weak hazard ratios, and poor confounders, really have no business being publicized to lay people to get them to change any aspect of their life.

This is certainly a problem with science reporting.

if we say we can’t test these things then we are not in the realm of empiricism but of theology

I would like to know how you think we've established the link between smoking and cancer. Or air quality, etc. It's just a tool, not something perfect.

theology

This is the key of my issue with your statements here. I am no vegetarian. When you are being hyperbolic like this, it makes everything else you say suspect.

[–] jet@hackertalks.com 1 points 1 day ago* (last edited 1 day ago) (1 children)

I would like to know how you think we’ve established the link between smoking and cancer. Or air quality, etc. It’s just a tool, not something perfect.

Ah, Good question! I do cover this in my evidence standards post (i know, I know, no time to read, but I'll quote the bits here) https://discuss.online/post/25820268

What about smoking? Smoking causes cancer and that was all observational epidemiology.

That epidemiology had hazard ratios of 6000 (far greater then 4), was consistent across different reputable studies, demonstrated in animal interventions… and most importantly there is no medical benefit to smoking… Giving up smoking is all upside, no real tradeoff. That being said… we actually don’t know that smoking causes cancer in all contexts - the health of the subject, their diet, their lifestyle, their genetics… there are smokers who die without lung cancer.


theology

This is the key of my issue with your statements here. I am no vegetarian. When you are being hyperbolic like this, it makes everything else you say suspect.

I'm not being hyperbolic, if the response to feedback about the rigor of something is that the thing is untestable, that is no longer science.


Depending on your lemmy interface there should be a undelete button too.

[–] echolalia@lemmy.ml 3 points 1 day ago* (last edited 1 day ago) (1 children)

That epidemiology had hazard ratios of 6000

Yes, fine, this is what I am saying: Take issue with the findings of the model, not epidemiological data (edit: as a technique that is akin to theology). Focus on that.

I’m not being hyperbolic

It was theology before, but now that hazard ratio is fine, because the number is big? There's big numbers in the bible too, friend. This is what I would call hyperbole. Either it's theology or it's not.

[–] jet@hackertalks.com 1 points 1 day ago* (last edited 1 day ago) (1 children)

Yes, fine, this is what I am saying: Take issue with the findings of the model, not epidemiological data. Focus on that.

I totally agree with you, actually.

Under what circumstances would I personally look at a observational epidemiology study and consider it to modify my behavior?

  • Hazard Ratios greater then 4 (far greater honestly, but 4 is the floor)
  • Absolute Risk reported in the paper (not relative)
  • Clear signal across different studies

However, this is so rare, that it is exceptional.

It was theology before, but now that hazard ratio is fine, because the number is big? There’s big numbers in the bible too, friend. This is what I would call hyperbole. Either it’s theology or it’s not.

It does not prove causation, there is no downside to giving up smoking, so why not? Does smoking cause cancer in all circumstances, no. So, give up smoking, sure why not. Does smoking cause cancer? It hasn't been proven.

There is more nuance here, in some contexts smoking is correlated with cancer. I have my own personal theories on the incidence of cancer increasing even though smoking has existed throughout documented history, but that is neither here nor there.

[–] echolalia@lemmy.ml 3 points 1 day ago (1 children)

there is no downside to giving up smoking, so why not?

To you there is no downside. People actually do take up smoking for reasons. For example, I have worked shitty jobs where smokers get extra breaks, or get extra time to bullshit with the boss. They also might do it because they feel it looks cool. These are not valid reasons for me (being that it is unhealthy, expensive, and messy). It sure seems like I'm being nit picky here, but this statement just isn't true! It's also pretty hard to quit if you've started, why bother doing it? The money may be less important than the downsides of withdrawals there. It's why it's important to point out that smoking is bad for you, and epistemological studies is one of the tools we have for that.

Similarly, people give up meat for reasons that do not make sense to you: It can be expensive, it can contain pathogens, industrial farming is a blight, etc etc etc. For them, the benefits do not outweigh the negatives. I'm not litigating this. I'm just pointing it out. I eat meat. This isn't part of my identity, it is the force of gravity for me. Eating meat is easy.

There is more nuance here

Incredible that you're speaking about nuance when you've just called epistemology theology. I mean I totally agree with you, the devil is in the details, but.... damn dude. :')

[–] jet@hackertalks.com 1 points 1 day ago* (last edited 1 day ago) (1 children)

epistemology theology.

Ah, I see our disconnect. I don't think of epidemiology as theology at all. I think of the abandonment of science throwing up all enquiry on a subject because its hard to test, but still using weak epidemiology to inform public policy, guidelines, and even lifestyle... that is theology.

Epidemiology is a tool that can be used in science, it is hypothesis generating after all, but by itself it is not science, it is a part of science, not the end of science.

Weak epidemiology can be engineered for any result you want... Paper - Grilling the data: application of specification curve analysis to red meat and all-cause mortality

[–] echolalia@lemmy.ml 3 points 1 day ago* (last edited 1 day ago) (1 children)

Yes, there does seem to be a disconnect here.

Using weak epidemiology to inform public policy, etc, is bad.

Calling epidemiology guessing, or saying that it's use is "not in the realm of empiricism but of theology" is hyperbole. If you're going to critique a paper because it's being presented to a layman audience, you should probably avoid that (that being: exaggeration. Don't do that.).

This has, more or less been my point for this entire comment chain. Your exaggeration is harmful to your overall argument. Especially because people take up a sports-team sort of ideological following for eating meat vs not eating meat. I'd be especially avoidant of exaggeration for that reason.

[–] jet@hackertalks.com 1 points 1 day ago

I didn't say epidemiology was guessing

I said the statistical controls for confounding variables are guesses. And that is true

I didn't say epidemiology was theology.

The abandonment of science, falling back onto week epidemiology is theology

I don't know how to express this more clearly