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When they warn of rare disorders, these prenatal tests are usually wrong

nytimes.com

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Re: When they warn of rare disorders, these prenatal tests are usually wrong

#141

Post by BoorishBears »

jacobolus wrote: post #139
BoorishBears wrote: post #134

Earlier quoted context omitted.

The entire comment you've written seems hellbent on attributing this person's anger to some specific entity... did you take 5 seconds to ask yourself what the goal of that is? Is the goal to find out what they're angry at so you can invalidate their pain over (what you seem to understand is) a terrible situation? "Oh you're angry at the doctors? Well doctors can't read the future." "Oh you're angry at the tests? Well…

I didn’t understand what they were trying to say (e.g. who is supposed to be "burning in hell") and asked for clarification. Asking people to clarify when their statements are confusing/ambiguous is a pretty normal part of human conversations, and is not as a general rule intended as an attack. Nobody has a secret agenda here. Nobody (except you?) is attacking anyone, correcting them, telling them they are wrong, pol…

The passive-aggression will only get you so far... here's the comment you seem to have already forgotten replying to:

> Anyone trying to shickle a few dollars from the medical system to provide "pre-natal diagnosis" without sound science - they can come burn in the same hell I live in every day.

Where's the ambiguity?! How much more clear could this be?

> Anyone trying to shickle a few dollars from the medical system to provide "pre-natal diagnosis" without sound science

-

Or is it that you don't understand why someone would be angered by people pedaling prenatal diagnosis based on unsound science for personal gain? And doubly so someone who experienced so much pain after these types of tests failed them?

> You seem to be really dramatically upset about this

So you can pick up an emotional cue! (Well... actually you still seem unsure despite me being very clearly upset, so still have some ways to go.)

Yes, I'm very upset I had to tell what I assume is a grown adult that casually asking people if they wish they had aborted their child is not ok!

And as I write that I have to say: if you actually do have some medical situation that affects your non-verbal skills, then I do apologize for being harsh.

-

Otherwise if you really want me to feel better soon, stop with the flimsy runabout and be better.

Re: When they warn of rare disorders, these prenatal tests are usually wrong

#142

Post by CorrectHorseBat »

sundvor wrote: post #135
CorrectHorseBat wrote: post #82

Earlier quoted context omitted.

The point is that it is a screening test. A positive test will be followed by a more invasive test that has a lower false positive rate.

"The good news is that the invasive test proved the screener was incorrect. The bad news is that it looks like you've now lost your baby. It was fine though!". The risks associated with this extended testing are just not worth it, perhaps aside from Down's (from a numbers point of view). Even then, there are many completely gorgeous children and people with Down's .. chances are you'll have a curveball in life one wa…

You are free not to take the test, but I think we would have taken the 0.3% risk to see if it is really Down's. While children with Down's can be gorgeous, I am not up to the task.

Re: When they warn of rare disorders, these prenatal tests are usually wrong

#143

Post by jacobolus »

BoorishBears wrote: post #141
jacobolus wrote: post #139

Earlier quoted context omitted.

I didn’t understand what they were trying to say (e.g. who is supposed to be "burning in hell") and asked for clarification. Asking people to clarify when their statements are confusing/ambiguous is a pretty normal part of human conversations, and is not as a general rule intended as an attack. Nobody has a secret agenda here. Nobody (except you?) is attacking anyone, correcting them, telling them they are wrong, pol…

The passive-aggression will only get you so far... here's the comment you seem to have already forgotten replying to: > Anyone trying to shickle a few dollars from the medical system to provide "pre-natal diagnosis" without sound science - they can come burn in the same hell I live in every day. Where's the ambiguity?! How much more clear could this be? > Anyone trying to shickle a few dollars from the medical system…

You are repeatedly making very strong, incorrect (quite aggressively insulting) claims about my intentions based on your own invented assumptions, despite having been told directly that you were incorrect.

You now claim that actually I am lying about what my intentions were. You insist that I was previously intending to be insulting and cruel and that by (a) apologizing for being insensitive and (b) denying that was my original intention I am being “passive aggressive”.

(To what end do you think I would do this, and who do you think my “aggression” is aimed at? You think I am just trolling you for my own amusement?)

I don’t see any way of convincing you otherwise here; continuing this conversation seems futile. Have a good day.

* * *

Edit: for the record, my top comment upthread is currently at net +25 votes. Apparently a whole lot of other people also found the top-level comment very confusing/ambiguous.

Re: When they warn of rare disorders, these prenatal tests are usually wrong

#144

Post by rscho »

derbOac wrote: post #99
jasonhansel wrote: post #68

IMHO, some of those criticizing the article for failing to understand statistics are missing the point. The point is that people who get a "positive" result on these tests are often put through terrifying levels of anxiety when there is no actual problem; this anxiety is often exacerbated because they aren't informed of the false positive rate. This clearly has a harmful emotional effect on people, and explaining the…

I've worked clinically and taught this in professional training programs. It's a classical clinical decision making problem. The solution is fairly straightforward I think: require the test companies to report the posterior probability of the illness given the test result. Probably with some kind of uncertainty interval.

The posterior depends on the prior. So not very feasible in practice.

Re: When they warn of rare disorders, these prenatal tests are usually wrong

#145

Post by sundvor »

CorrectHorseBat wrote: post #142
sundvor wrote: post #135

Earlier quoted context omitted.

"The good news is that the invasive test proved the screener was incorrect. The bad news is that it looks like you've now lost your baby. It was fine though!". The risks associated with this extended testing are just not worth it, perhaps aside from Down's (from a numbers point of view). Even then, there are many completely gorgeous children and people with Down's .. chances are you'll have a curveball in life one wa…

You are free not to take the test, but I think we would have taken the 0.3% risk to see if it is really Down's. While children with Down's can be gorgeous, I am not up to the task.

We did get the test for it for my two; can't recall if we did any extra ones. Believe we skipped them, at least on the 2nd.

I've come around to maybe change my mind since then, however I'd need to be in a very good position to be able to be up to the task.

I truly wouldn't have been, the ASD diagnosis was hard enough - and made magnitudes harder due to the manipulations of the "autism industry". Do this, do that, or else - you only have one chance for an early intervention, so better throw your own life away or you'll be a bad, bad parent.

Re: When they warn of rare disorders, these prenatal tests are usually wrong

#146

Post by d0mine »

CorrectHorseBat wrote: post #82
tinbad wrote: post #64

Earlier quoted context omitted.

Having gone through two twin pregnancies (where the odds of these tests being correct are especially low) we declined all of them. Anecdotally, I know of several parents who had a positive test for genetic disorder, went ahead with the pregnancy anyway and children were perfectly healthy. Until these tests are close to 100% reliable I don’t see the point.

The point is that it is a screening test. A positive test will be followed by a more invasive test that has a lower false positive rate.

Tests (the consequences) are not harmless e.g., https://empowertotalhealth.com.au/new-study-on-screening-mam...

Re: When they warn of rare disorders, these prenatal tests are usually wrong

#147

Post by [deleted] »

BoorishBears wrote: post #136
burnished wrote: post #127

Earlier quoted context omitted.

Disagree. I don't get your reading from it and frankly I read the above comment and also did not understand what they had intended to communicate due to seeming contradictions. I had the same questions.

My reading was being charitable, but I was corrected by the follow up. I wanted to believe this person understood the top level comment was venting and asked anyways (implying sarcasm) because that seems like a pretty basic inference from most people's social experiences. But instead they clarified they (and I guess you as well) truly do not realize that the top level comment is upset because prenatal tests were part…

[deleted]

Re: When they warn of rare disorders, these prenatal tests are usually wrong

#148

Post by midjji »

thaumasiotes wrote: post #104
midjji wrote: post #70

Earlier quoted context omitted.

If you get a positive for a horrid cancer with a 90 percent false positives you should be afraid. Its lunacy for tests to be regulated beyond requiring rough false positive false negative rates, and if anything smacks of "I dont understand statistics and therefore have to protect my children from understanding statistics." The article is most likely written by some anti abortion idiot.

> Its lunacy for tests to be regulated beyond requiring rough false positive false negative rates There is a good reason tests are described in terms of sensitivity and specificity ("if the answer in reality is yes, how often will the test say no?") rather than in terms of false positive or false negative rates ("if the test says no, how often is the true answer yes?"). The sensitivity and specificity are facts about…

For a test manufacturer you are right, and they aren't responsible for accounting for general population frequencies, or conditional frequencies based on things like some sibling has it etc. But there is no need to regulate that. But the serivice in question isnt a test manufacturer, its diagnostics, and they are responsible for this. I think a company selling a diagnostics service should be required to prominently display reasonably accurate FP,TP,FN,TN rates for gen pop, as the next example will show.

This is is not a legal problem, its a customer experience one, and as such its very much what the free market does well. A clever company could say that the tests service we provide works in a two stage process where a preliminary test is used to identify which conditions need to be investigated further, the results of which are presented in a meeting with one of our doctors were the results are explained and additional tests are performed to resolve any ambiguity. This combines the benefits of sensitivity, and specificity in a resource efficient way, and does not provide the user with any scary results before a certain answer is available. The FP,FN,TP,TN probabilities for gen pop for such a company would be much better than those of companies trying to do so in a single pass. But for these figures to mean anything regulating that they are available and reasonably accurate is key to ensure an efficient market.

Another problem is of course that the tests themselves are shit, or the rates based on poor data. The requirement on reasonably accurately reported gen pop rates help with this however, and I see no way around legally forcing diagnostic services providers to prove this. And until someone does, my patent pending algorithm(){return false} tests for all rare genetic disorders with excellent accuracy^^

Re: When they warn of rare disorders, these prenatal tests are usually wrong

#149

Post by OJFord »

thaumasiotes wrote: post #104
midjji wrote: post #70

Earlier quoted context omitted.

If you get a positive for a horrid cancer with a 90 percent false positives you should be afraid. Its lunacy for tests to be regulated beyond requiring rough false positive false negative rates, and if anything smacks of "I dont understand statistics and therefore have to protect my children from understanding statistics." The article is most likely written by some anti abortion idiot.

> Its lunacy for tests to be regulated beyond requiring rough false positive false negative rates There is a good reason tests are described in terms of sensitivity and specificity ("if the answer in reality is yes, how often will the test say no?") rather than in terms of false positive or false negative rates ("if the test says no, how often is the true answer yes?"). The sensitivity and specificity are facts about…

I'm not sure GP was intending to make that distinction (rates globally for the test vs. the sample population being tested by.. what a given doctor/hospital?) - I haven't come across that before.

If the population is the same then your changed-order definitions are just inverses, and they're just different terms for the same thing.

Re: When they warn of rare disorders, these prenatal tests are usually wrong

#150

Post by OJFord »

BoorishBears wrote: post #111
kryogen1c wrote: post #90

Earlier quoted context omitted.

you should probably step back and take a breather. youre emotionally involved in a matter with your kid(s) - as one should be - but thats not the way to have a public discourse.

The reply is pretty tasteless. Especially: > Suggesting you should have aborted the 20-week fetus based on unusual skull appearance? Suggesting that the meningitis was a result of some malpractice? Don't ask people sarcastic questions on a subject like this. You wouldn't do it in real life would you? It's a real person who just shared a harrowing experience with a child, not talking about the latest "Rust framework f…

Woah, that wasn't my reading at all, I also didn't understand top-level commenter's implication, as in what went wrong and should have happened, or what's regretted; no judgement or disbelief or whatever - I just didn't understand (not denying there was one) the failing that meant the test manufacturers should join the commenter in hell.
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