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$5 device tests for breast cancer in under 5 seconds: study

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Re: $5 device tests for breast cancer in under 5 seconds: study

#131

Earlier quoted context omitted.

> This is an unbalanced study. As such, it doesn't tell you anything about the ability to differentiate between the three populations. Complete Nonsense > That is not enough to be able to adequately know range of measurable values in the population of patients w/o cancer. True. But it is a promising initial signal that the distribution of non cancerous folks is probably very different from the invasive cancer folks.…

Look, you obviously have your opinions here. I'm not sure just saying "Complete nonsense" at things is really all that helpful. What I said ( "it doesn't tell you anything about the ability to differentiate between the three populations" ) is quite correct. This study shows that there is a difference between the groups of samples tested with their HER2 test strip, with a one-way p-value of ~0.002. I'm not convinced t…

> Look, you obviously have your opinions here. I'm not sure just saying "Complete nonsense" at things is really all that helpful. > What I said ("it doesn't tell you anything about the ability to differentiate between the three populations") is quite correct. This study shows that there is a difference between the groups of samples tested with their HER2 test strip, with a one-way p-value of ~0.002.

You claimed this was the implication of an unbalanced study. I’m sorry but that is a complete non sequitur. It is nonsense. Most of everything else I disagree with but isn’t nonsense.

> I'm not sure what they are trying to claim in there paper... are they trying to say that they can diagnose breast cancer (which would requires many more biomarkers), or are they trying to say that they can differentiate between HER2+ and HER2- cancers (which would be more appropriate for a HER2 test).

They are simply showing different distributions of tests for different populations and observing that, foremost, the invasive cancer ones have a significantly different distribution; and that it’s shows promise as a test for the future.

Re: $5 device tests for breast cancer in under 5 seconds: study

#133
I could not assess the validity of this paper if my life depended on it.

But this is what I do know: Given that the University of Florida is a public institution and the governor of the state is anti-science and promotes anti-science policies and practices, my immediate reaction to this paper’s news is negative. Reasonable? Probably not. I can’t be the only one who would react in this way.

This matters for two reasons. First, each of us has limited time and capacity to care about things, to investigate them more. Second, if we don’t recognize our biases, we may ignore important and useful information.

Re: $5 device tests for breast cancer in under 5 seconds: study

#134
post #57

Earlier quoted context omitted.

You can absolutely draw conclusions about the statistical power of the test. That’s what statistics is for. If this sample data is randomly sampled it looks like it will be a fairly high precision test for invasive cancers, with room for false negatives. You would have had to have gotten very unlucky to see such a difference in distributions even on a small sample like this. But sure, let’s get more samples.

Thank you for this! I get frustrated with the "N of only 21? Might as well flip a coin!" responses. Like you say, the whole purpose of statistical testing is to give an accurate, numeric value that says how likely the results are due to chance. One thing I'd note, though, is that the paper's title is "High sensitivity saliva-based biosensor in detection of breast cancer biomarkers: HER2 and CA15-3". My understanding…

If you only flip a coin to the same side 21 times in a row, it could just be chance!

It's only 1 in a million, but at about 10 the same I'd start to figure the coin wasn't fair.

Re: $5 device tests for breast cancer in under 5 seconds: study

#135

Earlier quoted context omitted.

First standout thing I noticed is the “patern generator” array of DIPs - admittedly without having dived into the paper, any answers from the hive mind what they’re doing?

I was focusing more on the "current to frequency" stage, which looks like an empty IC socket. As is the "pulse width counting" stage just a bunch of header pins? I mean yeah, I get it, it's a prototype and a finished product will be on a $2 ASIC to drive the correct signals and etc. But I'm not up to speed on affinity sensors vs. traditional ELISA tech so .

Yeah; it's a bit strange to label a single MOSFET...

Re: $5 device tests for breast cancer in under 5 seconds: study

#136
post #43

Earlier quoted context omitted.

"but even a few percent more early detections due to frequent testing would be a win" This is not the current medical thought on early screenings for various cancers. It used to be and I was confused about it until very recently. Indeed the medical community is still wrestling with the issue of screening harms. The consensus is shifting that screening should only be done if there is an existing condition or symptom o…

That depends on how harmful the screening is, how harmful treatment is, how harmful the disease is, how well the test works, and how common the disease is. (probably more that I'm not aware of) Most cancer treatments are really nasty. Thus false positives are really bad: you destroy someone's quality of life. The earlier cancer is discovered the better chance that we can use a less harmful treatment (if only because…

> Most cancer treatments are really nasty. Thus false positives are really bad

I was imagining this cheap self test like covid self tests: you don't start taking chemo, but it's an indication to see a doctor tomorrow if not today and get it checked out properly

But you do raise a good point about overtreatment which I had forgotten while writing my previous comment. Whether that applies to diseases that are reliable to confirm manually and will simply kill you if you're late to the party is another matter, but I had forgotten to take it into account at all

Re: $5 device tests for breast cancer in under 5 seconds: study

#137
post #130

Earlier quoted context omitted.

I don't believe they could run a battery of 81+ tests on a drop of blood. There simply isn't enough there. Why do you think they take tubes of blood for testing, currently? The issue is concentrations and the presence of them in sufficient amounts to be detected reliably and consistently. edit: typo.. words are hard.

It's because that's what the equipment is designed to use, and yes it provides more reliable results with the current technology. Much of the equipment used in healthcare relies on very old technology. This certainly does not mean it cannot be improved to work with less amount of material. There are hand held sequencers for your phone now (minIon) that are very cheap and work. There are also large multimillion dollar…

Less resolute works in some cases and that was never at issue. The problem is, less resolute doesn't work for some things and when the sample size is a drop of blood, we're talking insanely small, as in impossible, sample size for some tests.

Low concentrations will NOT be reliably detected. That's part of why such a comparatively large sample is taken when you go for the traditional testing.

I'm not even going into the simple fact that once chems are introduced into the sample to generate reactions, the sample can't continue to be used.

Exactly how many times do you think we can split a single drop of blood?

Edit: good talk, even if we disagree. :)

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