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Your take on Evidence Based Medicine (EBM) is wrong.

At the top of the evidence hierarchy is N-of-1 trials (and below that are high quality meta-analyses of trials). Nothing is more informative about treatment response in a person than testing it in that person. This is the heart of personalized medicine, and exactly for the reason you stated: Different interventions work differently for different people.

And any practitioner worth their salt is unsurprised by this headline. A great example is that illness and inflammation increase insulin resistance via counter-regulatory hormones.

You got one thing right, intuition often turns out to be wrong. That is why the vast majority experimental therapeutics built on great ideas never get passed initial testing.

It is wonderful that we have things like CGM's and patients can establish their own baselines and their own evidence profiles on a high(ish) frequency basis.

Such tools also enable studies that can be done at a scale and cost level that is reasonable and can push forward the communal knowledge base.

Yup, and this was the original dream of Theranos - lots of measurements, lots of data. It's a nice dream, shame about the lies though.

This is the idea behind the "Zoe" service: https://zoe.com/en-us

1. You wear a CGM for 2 weeks, and log everything you eat.

2. At the end, you get a personalized report about how different foods that you ate affect you, personally. And they can extrapolate to other foods that you didn't eat during the testing period.

3. Zoe's model gets better and better the more people sign up, and the more data they get.

> And they can extrapolate to other foods that you didn't eat during the testing period.

I would need to see an independent researcher confirm they can do this. As of now, I don't believe they can, and I'm not even sure the theory is reasonable.

This is the type of thing that the linked studies refute - there are either too many external variables to control, or our bodies glucose response is far more complex than we currently understand. Or both - both of the above seem possibly true at the same time.

Either way, if something as simple as eating a few bites of bacon before you eat your toast can change your glucose response, manually logging your meals for Zoe isn’t gonna provide enough data for any reliable extrapolations.

> Either way, if something as simple as eating a few bites of bacon before you eat your toast can change your glucose response, manually logging your meals for Zoe isn’t gonna provide enough data for any reliable extrapolations

I'm not sure - the fact that it does vary from person to person, doesn't mean there aren't groups of people for whom it behaves more predictably, which could be clinically useful.

A CGM is not easy to use reproducibly. The quality control of the manufacturers is not that good, the placement of the sensor (particularly if it is near a place where insulin injections have caused lumps under the skin, or if it is on the back of the arm, where there may not be a lot of flesh) may cause some troubles, the calibration process is dubious, since CGM readings lag blood glucose by around half an hour, rapidly changing blood sugar levels seem to confuse the monitors, and very high or very low blood sugars seem to cause the accuracy of the sensors to deteriorate noticeably a few days prior to their respective expiration dates.

And how do you know that the logs are accurate? The best subjects are incarcerated subjects.

All that said, it's a long row to hoe, and the monitors are definitely worth all the annoyances; they are way better than peeing on a strip of testape like we did back in the old two-holer. But science is very hard.

> So, you have a lot of people commenting here that this is obvious common sense

There's a lot of reductionist commentary that happens under these links primarily because people aren't reading past the headline or a brief skim of the article.

The topic might be common sense, but measuring and quantifying it with hard data is valuable.

The PR-massaged headlines usually omit the interesting parts and focus on something basic because they want to appeal to a wide audience, not because the study itself was so simplistic that it could be summarized by a headline.

The map is not the territory, if only more professionals and doctors read some Alfred Korzybski, the world would have been a better place.

> My other pet peeve with EBM is that it does a poor job of understanding that different interventions work for different people

This has not been my experience with doctors throughout the years. In fact, I'd say the opposite has been true.

In my experience, particularly when diagnoses are trickier, doctors are more likely check the efficacy of the current treatment and change things up if it's not working out.

> "So, you have a lot of people commenting here that this is obvious common sense"

You have this about everything, everywhere. It's a pet peeve how much stuff people will attribute to "common sense" so they can do the internet "I'm superior" thing.

"Wear sunscreen, it's just common sense". No it isn't. We evolved on Earth under the sun, we feel good when going out in the sun, it's bright and beautiful. Rubbing petrochemical distillate or industrially processed plant extract on your skin so the invisible light discovered in 1801 doesn't denature the invisible DNA discovered in 1869 is not common sense it's learned behaviour. Nothing much about Science is common sense, it took thousands of years from the dawn of Civilization until the Enlightenment era and still people can go through years of education and then choose to believe what we want to believe instead of what the evidence shows.

'Common Sense' is that the world is simple, designed for a purpose by a human-like mind one or two levels up from us on the power scale, and inhabited by life-like energies and spirits, some of them malevolent. Common Sense is that things which didn't happen today or yesterday will probably never happen. Common Sense is that things which happen together cause each other; if the relative comes to town and the crop fails then they are bad luck, if the relative comes to town and the baby is born healthy then they are good luck.

Why would it be any kind of 'common sense' - 'sound judgement not based on any specialised knowledge' - that glucose (1747) response differs for the same meal if you need a continuous glucose monitor (FDA approved in 1999) to find that out?!

You are using one particular "definition" of the phrase common sense. It does appear when I search as well. But so do others.

    knowledge, judgement, and taste which is more or less universal and which is held more or less without reflection or argument. As such, it is often considered to represent the basic level of sound practical judgement or knowledge of basic facts that any adult human being ought to possess.

Now with that definition some of what you said very definitely would no longer be the case as the above definition would seem to automatically "adjust with the times" so to speak in that what we might expect most adults to know and understand changes over the years, decades and definitely centuries.

Most? 50.1%?

To be fair, what I quoted said "any", so I guess they mean closer to 99.99% but I'm with you on "unfortunately common sense seems to not be quite as common as one might wish for" ;)

> "Wear sunscreen, it's just common sense"

And this isn’t even universally true. It’s tied to skin color. Sunscreen won’t do much for someone with extremely dark skin. In medical lit, “common” often refers to “white persons.”

If you think about it, Evidence Based Medicine is very much against Medicine 3.0 whereby individualized treatments/therapies are used.

Why?

Because evidence based medicine is often about broader problems, medicine 3.0 is about solving problems for a specific person. It could be a rare type of cancer that a specific treatment has been crafted for that person - in this case theres no evidence to say that exact treatment works, maybe the over arching therapy is backed by evidence but it feels like a trend away from needing strong evidence to back the application of the therapy.

How is treatment crafted? Will waving a crystal stick be a part of it?

Literally all medical practitioners are trained to take individual people circumstances into account.

Taking individuals circumstances into account isn't evidence based medicine though...

I agree 100% but sometimes you see studies that confirm not only common sense but also very well researched science that is frankly beyond the need for replication, and that definitely triggers a "wouldn't that money be spent more efficiently by trying to do something new instead?? feeling anytime I see one of those studies.

A counter-point, in a certain sense: when the conclusions of scientific papers (in these softer science fields), contradict common sense, they tend to be unreproducible; the ones which don't, are.

The problem with studying humans is, roughly, the central limit theorem doesnt work: properties of biological and social systems do not have well-behaved statistics. So all this t-test pseudoscience can be a great misdirection, and common sense more reliable.

In the case where effect sizes are small and the data generating process "chaotic", assumptions of the opposite can be more dangerous than giving up on science and adopting "circumstantial humility". (Consider eg., that common sense is very weakly correlated across its practicioners, but "science" forces often pathological correlations on how people are treated -- which can signficantly mangify the harm).

> when the conclusions of scientific papers (in these softer science fields), contradict common sense, they tend to be unreproducible; the ones which don't, are.

Citation needed?

I don't know what would lead to that conclusion. And it would seem to run counter to the entire history of the field of psychology, for example.

Can't find the citation, but remember gwern mentioning a study in one of his posts on replication that found that unintuitive findings tend to be both less replicable and more cited than intuitive ones.

Psychology is the field that is most hit with replication failures and has a slew of unintuitive results that turn out to be malpractice.

Psychology is also the field with a slew of unintuitive results that have been repeatedly replicated as correct. And what is "intuitive" anyways? What was extremely non-intuitive a century ago is common sense today.

So that's why I question the assertion. You're right that there are tons of replication failures, but whether intuition correlates with replicability way doesn't seem relevant. Especially when the point of so much research is to look for currently "non-intuitive" things, so of course that's where more replication issues might exist. It doesn't mean you should stop researching in that direction.