What Medical Tests Should Teach Us About the NSA Surveillance Program

First time accepted submitter Davak writes "In many ways finding the small amount of terrorists within the United States is like screening a population of people for a rare disease. A physician explains why collecting excessive data is actually dangerous. Each time a test is run, the number of people incorrectly identified quickly dwarfs the correct matches. Just like in medicine, being incorrectly labelled has serious consequences."

Comments

The crazy is strong in this one

[davebarnes]

You, sir, are a nutjob.

well duh.

[Gravis Zero]

the NSA is not concerned about infringing on people's rights and civil liberties. if we are going with medical analogies, i think the NSA would rather amputate than treat an infection.

No time to read TFA

[Sponge Bath]

After glancing over the summary, I'm fine with doctors are experimenting on terrorist dwarves.

It seems likely

[The Real Dr John]

That the NSA is not specifically looking for terrorists, although that is the convenient excuse. They are looking for all sorts of things, and that is why they are collecting everything. They are listening in on foreign diplomats to see what they are up to, they are eavesdropping on foreign corporations to give US companies an advantage in trade deals, they are digging up dirt on political enemies and protesters, and they are checking up on reporters to help keep them in line, and they are especially looking for whistle blowers who might throw some light on what they are doing with our tax dollars. All of these activities have been reported, so it doesn't take much imagination to realize they are collecting everything they can on purpose and for numerous reasons, most of which are not to the benefit of the American people. If the intention was to help the American people, they would be putting all that computing power into bioinformatics to cure cancer and other diseases that kill half a million Americans a year.

Re:It seems likely

[Livius]

If the intention was to help the American people

The goal is to benefit the bank accounts of a small set of the American people.

Sociopaths will flatter themselves that they got it close enough.

Re:Then what do you do then?

[BrokenHalo]

So you have no test and just let the virus spread?

You extend the analogy too far. In fact, the analogy in TFA, while interesting, has limited relevance. Yes, the danger and destructive effects of false positives are important in both medicine and national security, but where TFA mentions (almost in passing) that "The balance between privacy and security is always difficult", it sidesteps the simple fact that this surveillance is about neither. It is about control.

Let us not fool ourselves that the US (or any other) government is actually likely to prevent all (or any) acts of terrorism with these efforts. We have recent proof otherwise. Our various governments have simply seized on this supposed threat as a means to exert control - for no other reason than because they can.

Re:hmm...doctors just don't worfk as hard

[uglyduckling]

No, because the point is that the false positive results lead to more invasive tests (which in themselves may do harm), over-interpretation of other physical signs, worry etc.. The parallel with terrorism is that people end up on no-fly lists, get invasively searched and questioned, might get turned down for jobs or credit etc.. The uselessness of screening tests for low prevalence diseases is well known in the medical world, which is why tests need to be targeted to a high-risk population to have any value.

Flawed Analogy

[the eric conspiracy]

Correctly done, Medical testing is made more accurate by gathering additional data.

Basic tests are generally inexpensive but have a pretty high false positive rate. The key here is to have a very low false negative rate first and then minimize the false positive rate with additional tests.

If a positive result is obtained additional data is gathered using different tests aimed at eliminating the false positives. This additional testing is often more invasive and expensive, however it drastically reduces the number of false positives.

The premise this article is based on is just repeating the initial screening over and over. That's not what happens.

Re:Flawed Analogy

[Davak]

When you screen huge masses of people needlessly, almost all to all of your hits are going to be incorrect. Additional testing of these false positives are harmful. Biopsies, radiation, no-fly lists -- harmful.

Nobody is saying that we should never wiretap if we have evidence. That's testing a small population. The problem here is that we are wiretapping everybody to attempt to find evidence.

Re:Flawed Analogy

[anagama]

The problem here is that we are wiretapping everybody to attempt to find evidence.

Honestly, I think the Feds know that collecting huge amounts of random data makes the job of finding bad people harder, not easier. But the point of the program isn't about finding bad guys, it is mainly to create a repository of information that can be accessed whenever they want to silence critics.

They don't care if they send you to prison because of your activism itself, they just want you in prison. This data collection coupled with a Federal code base so vast and vague as to be unknowable, basically ensures that everyone is a criminal and makes it trivial to suppress dissent simply by rummaging through the data store, finding some random bit of nonsense, and charging that person with 50 years worth of bullshit. Or as Snowden would say, it's "turnkey tyranny."

Re:Flawed Analogy

[AthanasiusKircher]

When you screen huge masses of people needlessly, almost all to all of your hits are going to be incorrect.

Yes, this is something that apparently even most doctors don't understand. Suppose who had a simple problem like this:

1% of women at age forty who participate in routine screening have breast cancer. 80% of women with breast cancer will get positive mammographies. 9.6% of women without breast cancer will also get positive mammographies. A woman in this age group had a positive mammography in a routine screening. What is the probability that she actually has breast cancer?

The correct answer (calculated from Bayes' Theorem, or simple logic) is 7.8%. Most doctors cannot do this problem, and that not only get the answer wrong, but they often get it wildly off -- estimating the answer to be much greater than 50% (often 70% or so, probably from simply subtracting the two numbers).

If you don't believe me, have a look at this link. As the author says there:

usually, only around 15% of doctors get it right. ("Really? 15%? Is that a real number, or an urban legend based on an Internet poll?" It's a real number. See Casscells, Schoenberger, and Grayboys 1978; Eddy 1982; Gigerenzer and Hoffrage 1995; and many other studies. It's a surprising result which is easy to replicate, so it's been extensively replicated.)

The author here is being generous. I looked at these studies years ago, and many of them show only 5-10% getting the answer to such problems correct.

And if this is true of physicians, it's probably true of just about anyone else who encounters a lot of false positives and isn't used to thinking statistically. That means most people are very likely to draw incorrect conclusions about the prevalence of something when the false-positive rate is high... making those using the methodology assume that (1) their methodology is better than it is, and (2) that with more "assumed positives" from incorrect logic, the incidence of whatever they're looking for in the population is higher than it is.

Let's not be rational about this ...

[Alain Williams]

As your elected representative let me enlighten you as to why you voted for me rather than the other guy:

* I made good, powerful speaches. I went to some classes to help with this, it is more important that I dress in a good suit and have a strong voice than what I say makes sense.

* I avoided checking facts when making opinions. If you know the facts you realise that things are not black & white, but to express that makes people think that you are a ditherer, that you don't know what you stand for. Who wants a politician who, when asked a question instead of saying ''yes'' or ''no'' says something long and boring that starts with ''It depends'' ?

* Most of you don't look at the facts, you work on gut feeling and gross extrapolation. You remember that story in the local press last week about the thief from out of town who had green eyes, blond hair and a limp ? Yes: you are quite right to know that everyone from out of town with blond hair & a limp is a good for nothing crook and we don't want people like that round here!

* You people just want to be safe. You don't care what happens to out of townies, how hard we make it for them; or even foreigners -- some of who have a skin of a funny colour. They just don't matter!

* You don't really know what safe means, but are happy if you can still watch TV and drink beer when supporting your team. My predecessor did not do anything to make you realise that you can do something else, neither will I --so you will vote for me next time.

* In order to get on the short list for election I had to sign up to what the party says. They won't listen to a newbie like me, if I ask questions there are plenty of others to choose from who do what the party bosses say.

* Do you know how much I got in ''research grants'' and travel ''expences'' from the large corpotations? To say nothing about my fee for 2 days work a year as a consultant. I must not upset them by saying something that upsets them. All that money buys a lot of publicity as well as letting me buy that new yacht..

* I have a good friend who knows people, (I don't want to know why they are), but I got warnings of the other guy's plans and it was mighty useful when his campaign manager was caught in bed with that young ... that no one had seen before

So you see, I would be really silly if I upset the status quo and made you think for yourself.

Ultimately, the same motivation

[Rambo Tribble]

Whether excessive medical tests or excessive surveillance, the minions happily promote it to ensure their job security. If the patient or the society suffers, well, that's okay. Perhaps a bit regrettable, but okay.

Ultimately, a society that strenuously promotes competition also engenders a mercenary attitude. So, you see, the excesses of Wall Street are not that far removed from the excesses of the NSA, or Microsoft, to pick but a very few examples.

Re:Slashdot Propaganda Machine Working Overtime

[ericloewe]

Where's the "-1: conspiracy theorist" option?

Here's the same argument about drug testing

[nbauman]

Here's another doctor who made the same argument about testing for illegal drugs. Be sure to catch the distinction between screening tests and diagnostic tests.

http://www.kevinmd.com/blog/2013/07/drug-testing-considered-screening-tests.html
Should drug testing be considered screening tests?
Chris Rangel, MD | Conditions | July 12, 2013

... The problem of a false positive test is frequently encountered in the practice of medicine. Depending on the clinical circumstances and the nature of the initial test, follow up evaluation with more expensive and possibly more invasive testing is often required in order to verify the results. For example, an abnormality found on the chest x-ray of a smoker with a bad cough requires further evaluation. A CT scan of the chest, bronchoscopy, and even a needle biopsy to obtain a tissue sample for analysis are required before making a diagnosis of lung cancer and starting treatment.

However, the possibility of a false positive drug screen and the need for further testing and evaluation is rarely considered outside the context of clinical practice. Employers, school administrators, government agencies, and law enforcement can and do consider a positive drug test to be perfectly equivalent to an admission of illicit drug use. This frequently results in the administration of some form of punishment or corrective action being delivered without giving the accused the right to defend themselves in any way. Essentially, drug testing is an effective way to violate a person’s right to due process since most drug screening is managed by lay people in non-clinical roles who believe that drug testing is 100% reliable. But this would be the same absurdity as giving chemotherapy to the smoker with the abnormal chest x-ray without first trying to verify the diagnosis with further evaluation (due process).

The other problem comes from the mass drug testing of large numbers of people (either random or at the initial point of contact). The interpretation of the results of a medical test are never as simple as positive or negative. The statistical probability of a false positive or a false negative result must be considered in concert with the pretest probability....

Re:Then what do you do then?

[jc42]

Let us not fool ourselves that the US (or any other) government is actually likely to prevent all (or any) acts of terrorism with these efforts. We have recent proof otherwise.

It's no longer "recent" by media standards, but the (second ;-) attack on the World Trade Center is an excellent example. Much of the news coverage of the event is still available online, and if you dig it up and look at it, you'll see that several things stand out. One is that the US authorities were totally taken by surprise, and didn't have any idea what was happening until after the second tower was hit. However, it became clear in the first several hours that they'd decided who to blame. The reports from everywhere were full of "Al Qaeda" and "Osama bin Laden" (often badly mispronounced ;-), despite the obvious fact that they couldn't have collected the evidence in such a short time.

Over the following weeks and months, it also became clear that their ignorance was pretty much self-imposed. They had been warned about the specific perps by various other countries' security folks, and chose to ignore the information. This was in part due to a serious shortage of Arabic-speaking translators in the US military/security agencies. This was in turn due to their mistreatment of Arabic speakers, which the US has millions of. If you look into this, you'd probably also conclude that anyone fluent in Arabic would have to be really stupid (or suicidal) to volunteer for a translator job in those agencies.

The most parsimonious theory explaining this is that the US government isn't particularly interested in finding and blocking terrorists; they are mostly interested in using such things as a way of instilling fear in the general population. With this understanding, the government's "anti-terrorist" activities make a lot of sense.

(And, of course, treating the US government as some sort of unified, monolithic entity is a major mistake. There are lots of people in various government agencies who understand the situation pretty well. But they're generally not the ones in charge. Or if they are, they also understand that it's all to their own personal benefit. Or they keep quiet because they understand how "whistle blowers" are treated, and don't want that to happen to them. But we may hear from them after they retire. ;-)

Re:Then what do you do then?

[tylikcat]

That's not the precise argument, at least in a medical context. If the tests themselves and the responses to false positive have no significant medical downside, that's one thing.

But, let's say we starting giving all women yearly mammograms at age 16. Now, while this might reveal a very tiny number of additional breast abnormalities (many of which won't be cancerous) it's going to expose a lot of women to increased amounts of radiation, and while that amount of radiation is slight, that is likely to lead to a measurable increase in rates of cancer. If you're causing more cancer than you're catching, it's a stupid test, right?*

In addition, the response to false positives needs to be taken into question. Further procedures have their own medical costs. If you have a high rate of false positives leading to painful and hazardous procedures, that cost, too, has to be weighed against the value of catching those cancers early. ... and I will stop here as the breast cancer analogy in particular is one I can babble on about for a very long time. (My mother is a breast cancer survivor, and was diagnosed fairly young, which puts me in a high risk category.)

* One could make the argument that this is a very tight analogy, as if surveillance is increasing hostility towards the government by US citizens, and towards the country overall abroad, we could be creating a worse situation than we're addressing. I think this is a pretty strong argument applied to some of our foreign wars.

Re:Then what do you do then?

[jkflying]

You're ignoring the side effects from treatment of people who didn't have the condition, and the suffering they go through. In the breast cancer analogy, chemotherapy is terrible: it causes your hair to fall out, you lose months or years of life to something that wasn't necessary. The alternatives are radiation therapy and mastectomy, which are worse. So how many people wrongly getting their breasts removed, or getting chemo, is worth saving a single person's life?

This is true in military and intelligence situations as well. If law enforcement starts having negative side effects (think TSA nude scanners and groping, SWAT teams being called as pranks etc) then the negative effects on society are worse than the actual problems they would be preventing. Not only that, but if they aren't seen as helping, people will become less cooperative to law enforcement officials, which will further break down social peace.

Re:Then what do you do then?

[tnk1]

Using the US Government's attitude to pre-9/11 is not very fair. They ignored the evidence because they figured that perhaps there would be some hijacking or some fairly minor bombing. They were caught by surprise because they were complacent, but that doesn't mean that they lacked the information to know exactly who was responsible.

I'm not at all surprised they had the information that fact. There were likely people in the CIA and FBI trying to get someone to listen in the upper management levels for years. Now those executives wanted answers and they finally listened.

The only thing that happened with 9/11 is that the government got an attitude adjustment. George W. Bush wanted to completely ignore the Middle East, back in the day. Then the Middle East came to him.

Why is it that people want to see intricate plots in something that can easily be explained by heading down to the DMV and checking out the average initiative level of a standard government worker? There are no "plots", there is no "campaign of fear". There is only crass incompetence. Don't kid yourself. 9/11 was a tragedy of bureaucracy and political tunnel vision. Believing in some sort of fiendish plot is giving them far too much credit.

Sharpshooter Falacy

[IBitOBear]

You know, when people talk about who was warned about what, they completely forget the sharpshooter falacy. Warn everyone about everyone, then when some one does some one thing you can say "you were warned" because, in the huge pile of everything-squared you can find that nedle in the nedle-stack.

Now all the people who pointed at the nedle demand a bigger nedle-stack full of smaller and smaller nedles.

More signal. But more noise. And more noise per each increment in signal.

And more blame to go around.

There was a song, it has a point. "You have to hold-on loosly but don't let go". There was a movie, and it has a point "the more you tighten your grip the more systems will slip through your fingers." It's like there are all these old aphorisms and they came about for having truth within them. The truth of moderation.

More isn't better, it likely never was.