
Bias in the ER - sergeant3
http://nautil.us/issue/45/power/bias-in-the-er
======
Hasz

      They hadn’t bothered to consider statistically far more likely causes of an irregular heartbeat. In Redelmeier’s experience, doctors did not think statistically.
    

Statistics assumes independence, something that may be hard to come by in the
ER. Even when you start factoring in the covariance between conditions,
there's so many confounding factors it's probably difficult to tease out any
sort of significant r^2 for an individual patient

Instead, I would advocate for a pattern recognition method. Given a database
of x million patients, it's likely someone has had the same type of case
before, if not very similar. A sample would provide much less variable results
than the individual patient,making diagnosis more confident.

Such a system could be used to predict symptoms before they become symptoms,
saving time and preventing pain while serving to reduce hospital workload.
Figure out a way to standardize it in the intake, and let the system predict
what's wrong. It'll solve most of the cases, and identify new trends, leaving
human doctors to focus on the edge cases like the one in the article.

~~~
djsumdog
I had a professor in undergrad who worked on order entry research. He talked
about one of the problems facing Vanderbilt as far as scanning costs.

CT scans and MRI are crazy expensive. Trauma patient comes in, doc orders a CT
scan, it comes back and he says, "shit, this doesn't tell me what I need to. I
knew I should have ordered an MRI instead."

They used a decision tree learning algorithm and trained it using attributes
of incoming patients and which type of scan would have been the most useful.
Then they did a trail where ER docs would enter in patient information and
what they would have picked, but then defer to the algorithm's judgement
instead.

I can't remember the number, but they significantly reduced the number of
unnecessary scans.

~~~
nojvek
Just curious why are MRI and CT machines so expensive? They are the ultimate
tool for debugging the human body. Shouldn't they be very affordable?

~~~
wyager
Cost inflation in the US is huge due to a combination of red tape, CYA,
customers with good insurance subsidizing people with bad/no insurance, and
many other factors. There's no simple answer, unfortunately. No one is
entirely sure why medical costs are so high in the US. It doesn't appear to be
any one factor that people commonly blame.

Fundamentally, they don't need to be expensive; via private medical tourism,
you can get any sort of scan at a fraction of the US cost.

~~~
throwawaydbdksn
The problem is everyone gets paid too much. Our doctors salaries are far out
of line with most countries , we have the strictest drug pricing laws in the
world, and people love to sue. We also have a significant portion of the
population paying no medical bills while the rest is overcharged to
compensate. On top of that our health insurance is full of middle men like
"PBM's" that do nothing but raise costs.

The combo means docs, drugs, treatment, and insurance are all more costly.

A fix is hard to come by but would work something like this.

1)subsidize the cost of medical school increasing supply of MDS 2)pass laws to
protect physicians from frivolous lawsuits or at least limit damages.
3)disallow drug companies from advertising, ban rampant kickbacks to doc's
that prescribe their drugs 4)ban anti competitive practices that prevent
insurance companies from negotiating prices directly with manufacturers. 5)
provide healthcare centers of last resort(the ER) compensation for patients
unable to pay.

My last point is state specific and really controversial but it's based on
what I've personally seen.

States with a lot of illegal immigrants spend an enormous amount for
healthcare at the ER for these people. Around 1/4 of the people that came into
the ER I was familiar with were likely illegal and over 90% either gave a fake
name or never paid. The majority of those costs are passed on to those with
insurance. I lived in an area with probably 3% of the population were
undocumented.

Since the ER is healthcare of last resort they are forced to treat you even if
you give them completely false info with no intention of paying. Illegal
immigrants know this and preferentially go to the ER because they get treated
without probing questions or need to pay. They also already have fake ID's in
most cases so giving one to the hospital isn't a big deal. This enomous cost
gets buried because it's politically unpopular to say and because the hospital
just raises prices in everyone else to compensate.

~~~
ubernostrum
_pass laws to protect physicians from frivolous lawsuits or at least limit
damages_

Several US states have harsh caps on medical malpractice damages. They still
see massively-rising medical costs. And in uncapped states the rate of growth
in malpractice damage awards hovers very close to the rate of inflation of the
US dollar.

Which sort of destroys the argument that "frivolous lawsuits" and massive
damage awards drive medical costs in any significant way.

~~~
coredog64
It's less the actual damages as much as it the defensive medicine that occurs
because of the constant risk. If you show up with the flu, but it could be
some weird disease that shows up in an MRI, the incentive for the doctor is to
get you an MRI.

I used to believe in caps, but I think we could do better than that. Create a
no-fault insurance market that pays people without the hassle of civil trials.
That has the potential to allow medical professionals to be more open and
honest about mistakes they make (similar to the aviation industry). That, in
turn, would allow for data-driven decisions about how to make the biggest
improvements for the lowest dollar amount.

Oh, and while we're at it, how about a self-driving unicorn that runs on
rainbows...

~~~
hellohappy1234
100% agreed with this. This is an insightful comment. people have no idea how
much practice patterns would change if less defensive medicine could be
practiced. So much of the inconvenience of medicine exists because the
standard of care is extremely conservative to ensure minimal risk of
litigation. The few states that have malpractice caps really doesnt change
anything--those states just provide a good practice environment in rare
situations, but doesn't change the way that standard medicine is practiced
because that is developed out of state as a national consensus.

------
rscho
This article seems mostly a glorified praise of a top-med-school-doc, who in
fact is probably in no way exceptional.

Some points:

\- the cardiac arrhythmia and pneumothorax anecdote absolutely screams
"inexperienced staff on scene". Not performing basic imaging for car crash
victims, and furthermore thinking of a medical (vs. surgical) cause first,
would be absolutely laughable for any trauma/ER doc, and does not respect
standard care guidelines. Big trauma centers also means lots of resident docs,
more or less supervised. Additionally, the article does not give a lot of
details about the case, so judgment of this particular case from an armchair
is presumptuous.

\- Many medical professionals not only do not think statistically, they also
believe statistical studies to be less reliable than their own clinical
experience-based judgment, and often rightly so. People outside of the field
often miss how catastrophic the quality of medical statistics are. The end
result is that professors will cite the literature when it supports their
opinion, and will say something on the order of: "in my experience as a
clinician, it would be better to do such and such..." when it does not.

\- a serious and reliable approach to statistics is a priority concern of
today's medical system. The main problems are 1) inability to collect reliable
data, and 2) professionals with no statistical education analyzing said data.
This is changing, albeit very slowly.

~~~
JshWright
> Big trauma centers also means lots of resident docs, more or less
> supervised.

Yep, that was my thought as well. That sounds a lot like a resident who
started heading down the wrong path before the attending pointed them back in
the right direction. A 'teachable moment' of the sort that occurs hundreds of
times a day at teaching hospitals across the continent.

------
fencepost
As a completely trivial takeaway from this, now I want to start using tissues
to press elevator buttons in hospitals, and possibly bring along surface
disinfecting wipes to use on them as well.

~~~
Baeocystin
I wonder if this is why I've seen metal buttons more often in hospital
elevators than elsewhere.

[https://en.wikipedia.org/wiki/Oligodynamic_effect](https://en.wikipedia.org/wiki/Oligodynamic_effect)

~~~
spqr0a1
Unfortunately, just being metal isn't enough. Most metal surfaces in hospitals
are stainless steel, which can hold viable pathogens for a week or more.
Silver plating would sterilize some pathogens in as little as 5 minutes.

~~~
chimeracoder
> Silver plating would sterilize some pathogens in as little as 5 minutes

That would be very expensive for very little benefit - five minutes is more
than long enough for multiple people to use the same buttons at a busy
hospital during the day.

It's much better to promote behaviors like washing hands before touching food
or mucous membranes (like rubbing your eyes) and using alcohol-based hand
sanitizers when that isn't practical. That's why you see hand sanitizer
dispensers every few feet at (good) hospitals, and why infection rates
plummeted when hospitals introduced them.

In addition, never touch those buttons with the tips of your fingers. Use the
knuckle of your pinky instead - it's much less common to accidentally use that
to touch a mucous membrane later on, so it's slightly better.

~~~
spqr0a1
The importance of handwashing can't be overstated, it is one of the keystones
of sanitation and public health! Hospital transmitted infections would go way
down if staff followed all checklists to a T.

It's a matter of defense-in-depth. When the traffic is heavy enough to have
less than 5 minutes between contacts, how many more people would be infected
after a week?

As for cost, it would be more expensive but less so than you might think. With
how thin the plating layer is, even for heavy wear, the material cost is under
$500 per square meter. For small objects like buttons, door knobs, and hand
rails it's negligible compared to installation and other costs. By switching
to a cheaper base material it could even be cheaper over all.

~~~
Baeocystin
I agree with your assessment. Considering the constant work hospitals put
towards maintaining a clean environment, it seems only natural to use self-
sterilizing surfaces whenever possible, just as part of the overall system.

------
projektir
I wonder how much this is influenced by medical staff being overworked.

~~~
snowpanda
I think there's more factors than that. Air traffic controllers are very
overworked and they don't often cause collisions[1].

I think this part of the article is what the big problem is:

“Eighty percent of doctors don’t think probabilities apply to their patients,”

I've recently gone through 4 years of medical treatment, and it's still
ongoing. Only to find out this week that I have Lyme disease. Given that the
chances of getting Lyme where I live is relatively small, it was overlooked
for many years. I even asked doctors to test for it, but they refused. Meaning
I'm a direct example of doctors not considering non-regular cases. It cost me
over $20,000 out of pocket. Not to mention the other things it cost me.

I don't know if its a form of arrogance or how they are trained or a
combination of both. But can be life-destroying for patients to say the least.
The leading cause of death in Lyme patients is suicide.

[1] [http://www.businessinsider.com/air-traffic-controllers-
are-d...](http://www.businessinsider.com/air-traffic-controllers-are-
dangerously-overworked-2015-8)

~~~
rscho
As a matter of fact, their training could indeed have motivated their refusal
to test. The Lyme test not being perfect and the disease not being that
frequent in your area makes testing dubious, depending on the particular
numbers. In more scientific words: if the prevalence of the disease goes down,
then the positive predictive value of the test decreases as well [1][2].

[1]
[https://en.wikipedia.org/wiki/Positive_and_negative_predicti...](https://en.wikipedia.org/wiki/Positive_and_negative_predictive_values#Positive_predictive_value)

[2]
[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2540558/pdf/bmj...](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2540558/pdf/bmj00448-0038a.pdf)

------
wallace_f
I wasn't aware of this, from the article, which appears to me to be a very,
very big deal

> more people died every year as a result of preventable accidents in
> hospitals than died in car crashes—which was saying something

~~~
tim333
It's a new finding a quite striking if true

Estimates are ~250k/yr for medical error, ~30k road deaths for the US

[https://news.ycombinator.com/item?id=11627213](https://news.ycombinator.com/item?id=11627213)

You can hear the researcher talking about it here:

[http://www.bmj.com/content/353/bmj.i2139](http://www.bmj.com/content/353/bmj.i2139)

~~~
JshWright
The number of people killed by medical errors thing is a little controversial.
People who are about to die anyway get a lot of medical interventions (which
is more opportunity for errors, big small). If a patient accidentally gets an
extra dose of their antacid 48 hours before they die, is it really likely that
error led to their death? Because it would be counted in that 250k/yr
number...

~~~
tim333
Yeah there are question marks about the methodology etc. though it still seems
there are a lot of errors [https://www.pamedsoc.org/tools-you-can-
use/topics/quality-an...](https://www.pamedsoc.org/tools-you-can-
use/topics/quality-and-value-blog/BlogJune2116)

~~~
JshWright
Preventable medical errors are certainly something we should continue to work
to reduce (significant progress has been made over the past few decades in
that regard).

I'm not advocating complacency, just pointing out that many people think the
250k/yr number is substantially inflated.

------
theincredulousk
I'm just glad to read a story about smart people thinking about a hard
problem.

It's an excerpt from a book - I think the point is to get interested in the
question not draw a conclusion ;)

------
moxious
There's a book called "Thinking Fast and Slow" by Daniel Kahneman that talks
about systematic bias in human heuristic thinking.

> The more easily people can call a scenario to mind, the more probable they
> find it.

This is practically a restatement of the "availability bias" from that book.
It came to mind immediately when I saw the article's title "How can Medical
Professionals Avoid Making Assumptions That Lead to Mistakes?"

The answer is probably that they can't, because they're human. One can put
good processes in place, and do things like checklisting that dissuade people
from making fast heuristic decisions (which we know are systematically, and
predictably wrong). But people really hate stuff like that, doctors
especially, and so it's an ongoing cultural battle.

Doctors in this regard are no different than software engineers, or plumbers,
or any other human at work, they just get more attention when they screw up
because people die.

~~~
eraboli
One thing to note is that the social priming studies in “Thinking Fast and
Slow” are not very replicable [1]

1\.
[https://replicationindex.wordpress.com/2017/02/02/reconstruc...](https://replicationindex.wordpress.com/2017/02/02/reconstruction-
of-a-train-wreck-how-priming-research-went-of-the-rails/)

~~~
mvp
Are only 'priming studies' in doubt? Or are most of the studies in social
psychology in doubt today? The experiments and conclusions used to fascinate
me, but once you lose trust it becomes hard to believe again.

I used to think all these experiments are conducted on people vastly different
from me or the people I interact with, so those findings are not applicable to
me. But now it seems that those are not applicable even to people who are a
lot like the subjects of the experiments.

I'm probably having the bias where one under the influence of a single
significant factor ignores all the rest :).

~~~
pacificish
Maybe not all but here's another also with a reference to the priming
kerfuffle [http://andrewgelman.com/2017/02/18/pizzagate-kahneman-two-
gr...](http://andrewgelman.com/2017/02/18/pizzagate-kahneman-two-great-
flavors-etc/)

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singularity2001
endoplasmatic reticulum?

------
bnchdrff
Why did they replace instances of "fi" with the ligature "ﬁ"?

Maybe they can more easily check for other sites cutting/pasting their work?

