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i_love_limes ◴[] No.31900479[source]
Epidemiologist in training here... There are quite a few comments in this thread already jumping on the 'correlation != causation' train. While that is true, I'd like to clarify a couple things:

1. The journal article didn't suggest it was causal. But such a correlation with such a large population warrants publication and further research into causation.

2. literally the first thing that any epidemiologist would consider is potential confounders. There is a big list of covariates they included into their model here: https://content.iospress.com/articles/journal-of-alzheimers-...

There are quite a few things that can be done to alleviate potential false correlations: DAGs, prior literature, removing confounders, and including covariates are all things at disposal.

3. Such a large sample size + previously reported findings + an inclusion of enough covariates still doesn't == causation, BUT it's important to publish and shout about so we can then look into the potential biological underpinnings that may cause this. Which by the way, those experiments may still use data science techniques.

4. If you are actually interested, there is a whole topic of this called 'causal inference' with one famous criteria list called the 'Bradford Hill Criteria': https://en.wikipedia.org/wiki/Bradford_Hill_criteria. This list is often argued about.

5. If all of this information was new to you, please stop spouting 'correlation != causation'. You probably don't know as much as you think

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amacneil ◴[] No.31900747[source]
If they only intend to claim correlation, avoiding the word "linked" in the announcement would probably help with general public interpretation.

I feel like in English, "linked" usually implies some sort of potential causation, not just a general relationship. For example: "boyfriend linked to murder case".

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sudosysgen ◴[] No.31901380[source]
Correlations do imply a link, though. They don't imply causation, but in the absence of selection bias and with enough of a sample size, it is almost certain there is a link somewhere.
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zugi ◴[] No.31903206[source]
Indeed there is a link but we don't even know the direction of causation. I find it quite plausible that people with as-yet undiagnosed early-onset Alzheimer's forget to get flu shots.
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ncmncm ◴[] No.31903297[source]
Yet, you also find it plausible that people who spent years on this project would never have thought of that.

Your misplaced trust in your own plausibility filter causes you to make foolish posts on HN.

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Jensson ◴[] No.31903852[source]
> Yet, you also find it plausible that people who spent years on this project would never have thought of that.

I find it plausible that the few people who spent hours reviewing this paper didn't think of that, and that the people publishing the paper ignored it since ignoring it could help them gain more funding.

> Your misplaced trust in your own plausibility filter causes you to make foolish posts on HN.

It is foolish to believe that scientists does things properly. As an outsider you only see the outlier results, meaning that most of what reaches HN could be faked or statistical trickery or have simple explanations due to poor science since poor science is more likely to produce headlines, while most scientists could still do the right thing.

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ncmncm ◴[] No.31904205[source]
Scientists are very frequently wrong. Any scientist who doesn't admit that is none. One example is adjacent to the topic here, continued adherence to the amyloid beta hypothesis.

But their mistakes are generally subtle, and not what somebody who knows nothing about the subject invents in the first seconds after first hearing about the topic.

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1. native_samples ◴[] No.31908952[source]
We're talking about epidemiology though. Their papers routinely contain major, grievous errors that anyone can spot in five minutes. There might well be subtle errors too but it doesn't matter when the field is overrun with papers that are quite obviously invalid on their face to any outsider, yet none of the insiders care.

The primary COVID model that triggered lockdowns was full of programming errors. It had never been peer reviewed, and its prediction of deaths varied by 80,000 depending on whether you engaged a data loading optimization or not. It gave totally different results depending on available CPU features! There were no tests and the results had never been validated against anything. Outsiders pointed out these problems, and the team didn't care, nor did anyone else in the field of epidemiology.

That's just one example of many. Epidemiology is kinda like the phrenology of our era (one of quite a few). It's not built on a firm scientific foundation.