Link: "Health Care Myth Busters: Is There a High Degree of Scientific Certainty in Modern Medicine?"

post by CronoDAS · 2011-04-01T05:25:59.052Z · LW · GW · Legacy · 34 comments

A feature in Scientific American magazine casts some light on the troubled state of modern medicine.

Health Care Myth Busters: Is There a High Degree of Scientific Certainty in Modern Medicine?

Short excerpt:

We could accurately say, "Half of what physicians do is wrong," or "Less than 20 percent of what physicians do has solid research to support it." Although these claims sound absurd, they are solidly supported by research that is largely agreed upon by experts.

Scientific American often gates its online articles after some time has passed, so I don't know how long it will be available.


Comments sorted by top scores.

comment by Scott Alexander (Yvain) · 2011-04-01T11:32:24.755Z · LW(p) · GW(p)

Well, the good news is that between Robin Hanson's claim that we receive twice as much health care as we should and these guys' claim that "Americans only receive about half of recommended medical care", on average we're getting it pretty darned close!

Replies from: Daniel_Burfoot
comment by Daniel_Burfoot · 2011-04-01T17:44:06.473Z · LW(p) · GW(p)

Right. Also, since most published research findings are wrong anyway, it's not such a big deal that doctors don't know about them! Life is good!

comment by wedrifid · 2011-04-01T08:04:50.790Z · LW(p) · GW(p)

Here is what Eddy has found in his research. Give a group of cardiologists high-quality coronary angiograms (a type of radiograph or x-ray) of typical patients and they will disagree about the diagnosis for about half of the patients. They will disagree with themselves on two successive readings of the same angiograms up to one-third of the time. Ask a group of experts to estimate the effect of colon-cancer screening on colon-cancer mortality and answers will range from five percent to 95 percent.

An excerpt. Scary!

Replies from: Yvain, SilasBarta
comment by Scott Alexander (Yvain) · 2011-04-01T21:17:00.783Z · LW(p) · GW(p)

Unfortunately, Scientific American doesn't give any clues as to what study this information comes from, and my attempts to find it have all come up blank (anyone else have more luck?)

Of the two studies I can find on inter-rater reliability of coronary angiography, one shows greater than 98%, and the other shows high 90s. No doubt these are completely different types of coronary scans with completely different criteria for success than whatever Eddy was doing, but given the lack of pointers to the original study it's impossible to say exactly what's going on.

comment by SilasBarta · 2011-04-01T16:37:37.078Z · LW(p) · GW(p)

Double-scary when you think about how much education one must (legally) get before becoming a cardiologist.

There's a huge amount of waste somewhere in all that.

Replies from: jimrandomh, Raemon
comment by jimrandomh · 2011-04-01T17:28:51.310Z · LW(p) · GW(p)

As I understand it, medical school is very heavy on memorization - doctors are expected to absorb a huge quantity of data about procedures, medications, etc. So much memorization, in fact, that it's probably incompatible with a habit of model-checking everything. If that's true, then this would filter out the traits that medicine needs most to repair its practices.

comment by Raemon · 2011-04-01T16:56:06.271Z · LW(p) · GW(p)

Or the field really is that confusing, which wouldn't surprise me too much. You're dealing with variables that are constantly changing.

Replies from: SilasBarta
comment by SilasBarta · 2011-04-01T20:06:22.586Z · LW(p) · GW(p)

I'm pretty sure it doeesn't take 4 years of "whatever you feel like majoring in" in university before even starting med school, just to learn an angiogram classifier that a computer can probably outperform you on anyway.

At least, the English lit classes could probably be scrapped ...

Replies from: Raemon
comment by Raemon · 2011-04-01T20:20:11.601Z · LW(p) · GW(p)

When it comes to medicine, if computers CAN outperform the average person, we should probably be using computers anyway. (Yeah, that maxim applies to most professions, but most professions don't have lives on the line).

Replies from: SilasBarta
comment by SilasBarta · 2011-04-01T20:22:54.199Z · LW(p) · GW(p)

When it comes to medicine, if computers CAN outperform the average person, we should probably be using computers anyway.

Hey, if you want to get doctors to step out of the way on the grounds that a computer really can trounce their expert judgment, even in just a few domains ... well, you're going up against a lot of resistance.

Replies from: Raemon
comment by Raemon · 2011-04-01T20:33:23.157Z · LW(p) · GW(p)

Well, yeah. That will definitely be an issue, if not now then in a few years. But I also wouldn't be surprised if this was a genuinely difficult task, and I don't know that statements like "a computer can probably outperform you" are justifiable to throw around, unless you actually know that computers DO have a better track record at the task in question.

Replies from: SilasBarta
comment by SilasBarta · 2011-04-01T20:39:09.118Z · LW(p) · GW(p)

I hadn't read it myself, but I remember that there are a lot of stories like these in Ian Ayers's Supercrunchers and the success of simple algorithms over expert judgment and the resistance thereto. And Superfreakonomics mentioned the story of how hard it was to get doctors to wash their hands as often as necessary.

comment by EchoingHorror · 2011-04-02T18:37:17.387Z · LW(p) · GW(p)

Hurray! A portion of what physicians do has solid research to support it! There are ways that work; we just have to do those more often and other things not at all.

What if the 15% of doctors who can at least follow the numbers started a medical sub-community dedicated to making decisions based on solid research and standardizing the practice of medicine, then commissioned an independent study of their success rate? That could take objective models for treatment, spread them to those who understand how they work, then spread them to everyone else who can see them working better than an average physicians choices.

Individual doctors could be certified by their sub-community as users of the research-supported ways, and their value would increase, and more would join them.

comment by Bo102010 · 2011-04-01T17:43:50.504Z · LW(p) · GW(p)

Would a patient thus do better to research his or her symptoms online before going to the doctor's office, and then insisting on the treatment provided?

If so is there a good place to do this research? Are there good websites that are usually informed with up-to-date research on a variety of topics? I haven't had a health issue that's needed such research in recent memory, but if I did I would probably type my symptoms into Google alongside technical sounding words like "incidence," "epidemiology," and "differential diagnosis."

Replies from: Yvain, jimrandomh, CronoDAS
comment by Scott Alexander (Yvain) · 2011-04-01T21:27:14.760Z · LW(p) · GW(p)

Symptom checker programs and Google are good preliminary resources, especially if you want to figure out whether it's worth your time going to the doctor or not for something mild.

If you Google your symptoms, then go to the doctor and insist you have whatever disease came up on top, and tell the doctor ey's wrong if ey disagrees or wants to do further tests, then you become the kind of patient who doctors tell hilarious stories about in hospital cafeterias. These stories are rarely hilarious for the patient involved unless they have a very masochistic sense of humor.

The more honest symptom checkers will give you a list of many possible conditions that could be causing your symptoms. Unless you have something really obvious, most doctors won't be able to do better than a list until they've done tests. Symptom checkers usually don't adjust for your age, your past history, your current medications, or many other things that are very important for serious illnesses, and they can only give a very probabilistic result. They have their place but in a serious condition are no replacement for a doctor.

Replies from: saturn, Emile
comment by saturn · 2011-04-01T23:03:47.459Z · LW(p) · GW(p)

On the other hand, without some kind of prompting, many doctors tend to narrowly focus on reaching a firm diagnosis at the expense of maximizing benefit/minimizing risk to the patient.

Replies from: Yvain
comment by Scott Alexander (Yvain) · 2011-04-02T11:13:32.481Z · LW(p) · GW(p)

There are certainly different schools of thought possible on how much time to invest in disease identification before going for a treatment, but can you explain your evidence for why you think most doctors tend to err on the side of over-caution?

Medicine does include the ideas of "empirical treatment" and "empirical diagnosis". Empirical treatment is when eg a doctor can't figure out exactly what a disease is, but it looks bacterial, so ey'll throw some common antibiotics at it and see if it works. Empirical diagnosis is when a doctor isn't sure about a particular diagnosis, so ey gives the treatment for that diagnosis and then if the patient gets a bit better ey's convinced and moves on to more serious long-term treatment.

These are useful but still not as good as knowing what you're doing. First of all, a lot of the time they complicate the picture enough to make real diagnosis impossible; an organism that could have been cultured and identified before starting empirical antibiotics might be decimated enough to become unidentifiable afterwards, but not so dead that it can't bounce back and cause a relapse, so starting empirical treatment can be dangerous if you think you're ever going to change your mind and want to figure out exactly what's wrong.

And a lot of time, the treatment for one disease will make another similar disease worse. Steroids are the best treatment for a lot of auto-immune conditions, but they will make infectious conditions worse; immune conditions can look like infectious conditions if you haven't investigated them properly; this is especially true in rashes, which some doctors prescribe steroids for almost automatically. With rashes it's not the end of the world because even if a rash gets worse you probably won't die from it, but it still annoys patients and there are some other conditions where you don't have that margin of error.

There's also just the common sense problem of people getting really angry if they've been told they have a disease, they've changed their life around to help live with that disease, they've been taking medicine for that disease which may have all sorts of side effects, and then they go to a second doctor and that doctor tells them they don't in fact have the disease. I saw a lady the other day who for eleven years thought she had multiple sclerosis, switched neurologists, and then the new neurologist told her she didn't have it - that's an extreme and very rare example and I have a feeling the error is with the new guy rather than the old guy, but even if so that level of uncertainty and confusion is still traumatic and is a good reason for doctors to work really hard to get a firm diagnosis before giving it.

Maybe I'm missing your point; if so can you give an example of what you mean?

comment by Emile · 2011-04-02T12:05:32.257Z · LW(p) · GW(p)

Symptom checker programs

Any recommendations for those? Google returns a lot of results, and I don't really know of a good way to filter between them. I didn't even know such programs existed!

Hmm, iTriage for Android looks like it has good reviews.

comment by jimrandomh · 2011-04-01T18:33:55.082Z · LW(p) · GW(p)

If you're willing and able to read medical research directly, search PubMed:

comment by CronoDAS · 2011-04-01T19:23:16.630Z · LW(p) · GW(p)

I don't know how good it actually is, but appears to be trying to do this...

comment by knb · 2011-04-01T21:21:29.495Z · LW(p) · GW(p)

The interesting thing is that, although Doctors seem to add little net value, their pay is very high.

Replies from: Manfred
comment by Manfred · 2011-04-02T04:13:14.663Z · LW(p) · GW(p)

I'd say a healthy person has a lot of added value compared to a sick one.

EDIT: Clearly a controversial sentiment, I know.

Replies from: SilasBarta
comment by SilasBarta · 2011-04-04T15:16:21.515Z · LW(p) · GW(p)

I think you were modded down for insinuating that the issue is simply one of whether "healthy people are better to have around than sick people", and thus that knb is trivializing the value of healthy people. This is a ridiculous position to impute to someone, and doesn't help the discussion.

knb's point (on any charitable, contextual reading), is that doctor's aren't responsible for most of the health that exists ("Doctors add little net value"), not that "making people healthy adds little value". Comments like yours -- tarring people who dispute the value added by much of mainstream medicine as "against health" -- seriously degrade the debate over this important issue. While we might not have much impact on the "demogogues in the wild", a comment like yours certainly warrants the disdain it received here.

Replies from: Manfred
comment by Manfred · 2011-04-04T17:41:04.046Z · LW(p) · GW(p)

My point (on any charitable, contextual reading) is that there is no necessary reason why doctors do not add value, and so simply asserting that they don't without further support is bad. Good ol' charity and context.

Replies from: SilasBarta
comment by SilasBarta · 2011-04-04T18:44:56.383Z · LW(p) · GW(p)

No reason but the Hanson research that others were referring to in the er, context of the thread. If you prefer to just characterize those who disagree with you as failing to see the value of healthy people, that's up to you.

Replies from: Manfred
comment by Manfred · 2011-04-04T23:25:43.416Z · LW(p) · GW(p)

Show me where in the Hanson piece there's a comparison between the value created and the pay of doctors, and I will admit that I was totally at fault.

I don't "characterize those who disagree with you as failing to see the value of healthy people." Careful not to try and read my mind. And since tone is really hard to convey over the internet, looking back on it my edit was a really awful idea. People didn't like my post because they just saw the literal meaning and didn't feel like being charitable, and I shot back with irony. Talk about guaranteed to fail.

EDIT: Actually, don't worry about reading my mind, especially when said reading just means interpreting my words literally (although I did deny that interpretation). I'll try to worry about making my mind more readable.

STILL EDIT: A quick guide to the meaning of my edit to my original post:

"Clearly a controversial sentiment, I know," when interpreted literally, means that I think people downvoted because they didn't value healthy people.

Hints that there is another meaning:

The dumbness of the literal interpretation. However, this hint was a total failure; if people didn't assume my intelligence enough to look for more meaning in the original post, why should I expect them to look for more meaning in the edit? In fact, peoples' impression of my dumbness should be reinforced by attaching a seemingly dumb edit to a seemingly dumb post.

The odd "I know" at the end. What purpose does it serve? Calling unnecessary attention to certainty is a fairly good way to signal irony - at least in the spoken word, where all sorts of other cues are going on. But in text it's not enough, at least if not played up far more.

"Clearly a controversial sentiment, I know," when interpreted ironically, means that I am entirely aware that it's not a controversial statement, and is a bit of a joke about my dumbness via the literal interpretation. However, it's also a big signal that I am, despite appearances, fully aware of what I said, and that I am prone to use more than just the literal meaning.

If people had realized this and then applied it to my original statement, they would have gotten my message. Unfortunately it was pretty damn inaccessible, especially since the people who I wanted to send it to were also the people who were least likely to find it.

comment by drethelin · 2011-04-01T16:37:29.117Z · LW(p) · GW(p)

Is there an established procedure for fixing an entire profession? What's the solution if almost all doctors are wrong about a great many things? I suppose changing Med School to produce new more competent doctors could work, except then every new doctor has to work with old doctors as soon as they graduate that do things in a different and worse way.

Replies from: TheOtherDave, DanielLC, nazgulnarsil
comment by TheOtherDave · 2011-04-01T16:43:40.078Z · LW(p) · GW(p)

This article, about the process and results of incorporating standard checklists into medical procedures, seems like a reasonable example of a success story and makes me wonder how many improvements could be implemented, not so much by making more competent doctors, but by pushing the cultural idea that doctors, like programmers, are technical specialists who operate best as part of a team that includes competent project managers.

comment by DanielLC · 2011-04-02T04:00:01.337Z · LW(p) · GW(p)

Start a business that does it right. If you can get past the regulators and such, and there are enough rational customers, you'd do better than everyone else, and they'd start copying you.

Replies from: Vladimir_M
comment by Vladimir_M · 2011-04-02T05:14:38.006Z · LW(p) · GW(p)

Start a business that does it right. If you can get past the regulators and such, and there are enough rational customers, you'd do better than everyone else, and they'd start copying you.

Well, good luck getting past regulators in a profession that operates as a self-regulating guild!

In my opinion, the only mechanism of competition that could conceivably ameliorate the systematic problems of medicine is the international medical tourism. However, I'm far from certain that free competition has much potential for preventing medicine from drifting away from reality, considering how much people are prone to biased and even outright magical thinking on this subject, even when all the incentives to get things right are in place.

Replies from: DanielLC
comment by DanielLC · 2011-04-03T17:56:14.172Z · LW(p) · GW(p)

I think business have to be more rational than people in general. If you pay for your own health care, this would be a problem, but if you have health insurance, they'll just pay for what works.

Replies from: Eugine_Nier, Vladimir_M
comment by Eugine_Nier · 2011-04-03T23:07:09.055Z · LW(p) · GW(p)

If you pay for your own health care, this would be a problem, but if you have health insurance, they'll just pay for what works.

This is more-or-less the reason health insurance companies are so hated.

comment by Vladimir_M · 2011-04-03T23:29:11.608Z · LW(p) · GW(p)

Not necessarily. The whole rather absurd U.S. institution of employer-paid health insurance is an artifact of various government-imposed incentives whose roots range back to WW2-era wage controls. The employers are artificially incentivized to pay a part of the wages in medical benefits instead of cash -- and if the employees value spurious medicine, there is no good reason for the employers to argue with their misconceptions. They'd happily pay part of the wages in astrological benefits if there was a comparable demand and regulatory incentive structure.

Of course, the employers would like to limit their overall expenses on medical benefits, but it's far from clear that questioning the effectiveness of medicine is a practical way to do so, especially since it's a strong social taboo. The idea of philistine and profiteering capitalists questioning the opinion of the wise and noble medical profession sounds blasphemous to the modern public opinion, and this could result in many bad consequences for the former.

comment by nazgulnarsil · 2011-04-01T23:32:21.584Z · LW(p) · GW(p)

start over in a new country. over time health outcomes will drive immigration.