91–100 of 137 posts
The PCB picture above the words "...The printed circuit board used in the saliva-based biosensor,..." makes me think the article is a scam. As a electronics engineer the word labels seem to be not especially relevant to the invention. Who makes boards with lots DIP chips?
I mean… even if we were talking some special hardware, that’s still PLC territory.
My reading was this isn’t $5, but could be made to be $5.
This is clearly a prototype.
Using the performance in the paper, the false positive rate means the current test in clinically useless (due to harm from screening and follow-up). Refining the test requires improving the selection of biomarkers and antibodies, not the hardware (which looks great).
Through hole DIP array? This is a prototype and it makes me skeptical of the whole thing. There is nothing a single $5 FPGA couldn’t do. So why not start there? I suspect because the people that made this doesn’t know electronics or programming well - but then also didn’t find someone that did.
This was put together the way long way, and it’s strange to me.
The "press release" looks more like a final report for a microcontroller applications class than an actual press release.
The thirty through hole parts made me the think the same thing.
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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?
From the paper: > Synchronous voltage pulses are sent to both the electrode of the strip connecting to the gate and drain electrodes of the MOSFET. The drain pulse is applied for around 1.1 ms at a constant voltage. The gate pulse starts at 40 μs after the drain pulse and ends at 40 μs before the end of the drain pulse. > the antigen-antibody complexes undergo stretching and contracting, akin to double springs, in re…
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Yeah, this looks like an Apple IIe logic board to me.
Commodity logic ICs ubiquitous and totally capable if needs are well-matched; it’s perhaps a deliberate prototype engineering/development choice.
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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…
>about 1 in 3000 cases of breast cancer discovered by xray wouldn't have got breast cancer in the first place without the screening I had no idea the risks associated with xrays for breast cancer screenings were that high. Do you have a source (for that 1:3000 assertion) I can read?
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A device such as this would never replace an MRI scan. The information provided is for screening purposes, at best. Also, diagnosis would typically be done using a mammography. The cost of such a scan is lower - around $100[0]. [0] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4142190/
Diagnosis is done via biopsy.
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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.
And this result probably helps the funding to get more patients. I’ve never worked in clinical trials but it seems like it would be so tiresome.
You can find my published papers here:
https://scholar.google.com/citations?user=5DdrMc8AAAAJ&hl=en
Press release: https://publishing.aip.org/publications/latest-content/would... Actual publication: https://pubs.aip.org/avs/jvb/article/42/2/023202/3262988/Hig... Experiment size is literally N=21, with 4 healthy participants, 3 in-situ breast cancers, and 14 invasive breast cancers. N=21 might as well be useless in my opinion. You can't draw any meaningful conclusions about statistical power of this test; if your pr…
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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…
A normal human fallacy is to focus on the thing you understand, that is easy to understand (e.g., easy to quantify), and overlook the difficult issues that are far more important. There is much more, of much more importance going on in most of these studies, and in their statistics and validity, than the sample size.