What's inside a digital pregnancy test (2020) | Hacker News Reader

What's inside a digital pregnancy test (2020)

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100 pointshubraumhugo54 comments

This has come up before, there are legitimate arguments for and against this but I’m included to side with the for (certainly after going through the process with my wife twice). LFTs are hard to read accurately, people are very bad at it. It’s something like 25% of the time people get it wrong. It is incredibly important that diagnostic tests are engineered to be as accurate as possible, removing human error is a legitimate engineering solution.

I suppose now we have all spent the last year regularly using LFTs maybe we are better at reading them? That would be an interesting study.

There is a startup here in the UK that’s doing LFTs read with a smartphone camera, they have a calibration graphic next to the result window ensuring a accurate reading. That solves the disposable electronic problem while using electronics for the reading. (Will come back and edit if I find them)

EDIT:

kalleboo found a citation for the ~25% false reading claim:

https://news.ycombinator.com/item?id=30231703

EDIT 2:

I think this is who I read about before doing the smartphone read LFTs:

https://www.sensynehealth.com/magnifeye

There's not only the woman happily waiting in her own home and lit bathroom for two stripes. There's also the woman being in a shitty situation doing the test in secret dreading the second stripe.

I guess your wife (and mine, for that matter) belong to the first category and it's just common to do such a test at the end of the cycle. I doubt women of the second category care for getting experienced in reading the tests.

Exactly, some woman may be in a situation where an inaccurate reading from that one test they can afford could result in a seriously bad domestic situation.

You may also have seen Vessel Health?

The co-founder gave a speech at the 2022 Advanced Lateral Flow Conference.

https://vesselhealth.com/

I remember this discussion coming up at least once before. AFAIR the argument was that many people had problems interpreting the test strips (not waiting long enough, mixing the results up). So they built a more foolproof way of reading the strips, which then tells you exactly what's up in simple words.

Edit: Turns out there's a response in this thread that says the same and in better words. [1] Man I hate twitter UI.

[1]: https://twitter.com/RealSexyCyborg/status/130178603213683507...

I do think that this is a lot of electronic waste which we should be avoiding, but the marketing / promotional activities are quite interesting in that the pitch to consumers is around it being comforting.

> Even if you’ve done one before, taking a pregnancy test is a very emotional time – you can feel a real mixture of conflicting emotions, ranging from nervousness to anticipation which can make for a pretty stressful experience. Those few minutes of waiting for your pregnancy test result can feel like the longest of your life, and time seemingly stands still.

> Clearblue DIGITAL Pregnancy Test with Smart Countdown is the only pregnancy test which reassures you from start to finish. With its robust, 50% wider sampling tip, integrated unique Smart Countdown to your result and clear Digital ‘Pregnant’ or ‘Not Pregnant’ results in words you will be reassured right up until your result.

I do wonder if there is another way to provide these assurances and comfort without having to put electronics in the thing - it feels like all of this could be solved just with good design in the normal standalone version (particularly as everyone has been practicing on lateral flows for the last few years!).

> I do wonder if there is another way to provide these assurances and comfort without having to put electronics in the thing

Yes - by ensuring the education system (both school and continuing adult education) is actually capable of producing residents who are able to follow instructions and is run by competent educationist instead of letting local marginally qualified busy bodies control it. Making instructions easily accessible eg. through a QR on pack linking to video on unmetered network. Widely teaching people how to use QR etc.

In many developed countries with good education systems, most people - even elderly and school students seem to have no problems correctly self administering Covid Rapid Antigen tests which is likely same order of magnitude stressful.

Especially women in shitty situation do do those tests in secret in badly lit environments.

Of course, education is gonna help and reproductive health and contraception are incredibly important. But up to the point where problems in this department are eradicated, some women will need easy-to-read tests.

> Especially women in shitty situation do do those tests in secret in badly lit environments.

Not that I'm not sympathetic but many problems in the US that common people face seem to be either a result of continuation of either hyper-local governance that seems to be a relic of "settling the continent" era OR an extreme form of capitalism that seems to be a relic of the "robber baron" era.

For the extra $2.61 this doodad costs, the lady could buy a light bulb or something.

Little diod light can be even cheaper and bright enough.

Yes but an electronic pregnancy test is cheaper and doesn't require getting congress to agree to pass any laws in improving education nationwide

> it feels like all of this could be solved just with good design in the normal standalone version

Let's be real 2 seconds here, the only reason this "upgraded" test exist is because it's more profitable than the regular one, this isn't a problem to solve (from the company's perspective). The entire thing revolves around the existence of an "inferior" version. They're going for 10x+ times more than a "dumb" test. It's pure marketing, they're preying on emotional people going through an emotional phase of their lives by selling them a pee stick that's supposedly going to "reassure" them.... this is marketing 101

Something can be both better and overpriced. This thread is weirdly fixated on cynical reasons being the only thing worth discussing here.

I think you've summed up all online discussions since the invention of networking. Be cynical of everything. Always ascribe malice first.

> I do wonder if there is another way to provide these assurances and comfort without having to put electronics in the thing - it feels like all of this could be solved just with good design in the normal standalone version (particularly as everyone has been practicing on lateral flows for the last few years!).

There is none, because the "assurances" are there to explain why is the device needed. The whole point of them is to explain to you that you might be confused by non-electronic test and therefore you need to buy this device instead.

Otherwise said, it is not about reassuring you nor about showing you how to read the test. It is meant to make you doubt your ability to read the traditional test correctly.

Nobody has problems with traditional pregnancy tests. Pretty much anyone can use them.

The only problem is waiting long enough to make sure they are be correct (5 days before period is due is meaningless for women with irregular periods), but the digital one doesn't help with that.

> Nobody has problems with traditional pregnancy tests

[citation needed]

https://archive.is/20081206110632/http://archfami.ama-assn.o...

> In a 1993 study from France, [...] Of the 478 positive (pregnant) urine samples distributed, 230 were falsely interpreted as negative (sensitivity, 48%)

> Valanis and Perlman [...] The incidence of false-negative results in this study was 24.3%.

Your link doesn't work for me, but I found a link to the study that does work: https://ajph.aphapublications.org/doi/pdf/10.2105/AJPH.72.9....

While the study does show that pregnancy tests in 1993 were very inaccurate, there is nothing in the study that suggests the inaccuracy was due to people having problems interpreting the result of the test. They are only hypothesizing about reasons for the inaccuracy, and they think that the biggest factor is that women did not wait long enough, which is pretty much what I said.

I strongly doubt that these computer based tests are in any way better than analog tests, especially since the electronics just add another potential point of failure, and they do nothing to address all the other issues with pregnancy tests.

I know a few people who dont wait 15 min on covid tests, and I know a guy who was tested posted positiv, but the line really only could be seen after 15 min (light pink, so background really needs to fade). So ppl not using these types of tests is a thing.

Wow, Twitter really turns everything political and toxic these days.

Yeah, can't believe how nasty those answers are.

«I get the "I have a vagina, therefore I have to be careful of people trying to scam me." part- but then you say "would this be useful to someone else?" if you have a shred of empathy.»

As if questioning something for possibly being a shady marketing strategy is the same as not having "a shred of empathy".

She could have explained it without being such a condescending d-bag.

I urge everybody who thinks these tests are always easy to read to look at this page where women are indeed seeking help on interpreting their tests: https://www.countdowntopregnancy.com/pregnancy-test-gallery/...

The comments are very interesting and you should take a peek. Helpful commenters are using image editing tools to check out whether the second line is actually there or just imagined.

A second stripe means a life-altering situation and with regards to access to terminations, time is very much of the essence.

Agreed. The sort of reductionist takes in here that blame education or illiteracy indicate a lack of experience.

Unfortunately in these borderline cases the only way to know for sure is to wait a few days and try again or set up a doctor's appt to get a better test.

Having these additional few days or not having them is incredibly important, depending on your jurisdiction.

In Germany, for example, for abortion (without medical indication) to be penalty-free you have to have a so called "pregnancy conflict counselling session" and the doctor's appointment all within a certain timespan. Now during covid, many of those doctors and the counselling services did not operate or only in a diminished capacity.

Those few days are nothing to sneer at.

Of course, another solution would be better/non-penalized access to these services and better preventative health care. But we're getting nowhere by just pointing at root causes without the radical action to change them.

I get the desire for the clear binary answer from seeing lots of similar problems with COVID tests. But if I bought this test I'd feel a bit scammed, I'd expect some magical fully digital process, the borderline results still exist with this system but are hidden, it kind of ruins it if you know that.

Could you elaborate a bit? I must be doing something wrong because most (9 out of 10) of these look negative (single stripe) to my eye on my monitor. Am I wrong about that? Or are you trying to point out that obviously negative tests still cause confusion and conflict in many of the users?

I guess the unsure ones are not the best example, though there are a few with incredibly faint lines. Maybe look at the positive ones. There are quite a few where I would strugge: https://www.countdowntopregnancy.com/pregnancy-test-gallery/...

The fact that the site provides on-line tools to change contrast, etc., is telling in itself.

But here are direct comparisons between an analog an digital ones:

* https://www.countdowntopregnancy.com/pregnancy-test-gallery/...

This is exactly the kind of engineering this world needs during a global semiconductor shortage...

How about a bluetooth enabled covid test? The digital pregnancy test really isn’t complete with a radio transmitter if you ask me.

https://hackaday.com/2021/10/17/electronic-covid-test-tear-d...

My go-to COVID tests are Bluetooth. IMO it's a pretty effective way of doing it, although I'd prefer wifi (the results take ~15 minutes and it'd be nice to not have to wait in person to get results)

Or blockchain

If you think about it, this actually makes sense: you have already been producing the paper strip tests for years, they are accurate, so if you want to have an electronic version, why not use the paper strips? Another testing method (whichever that may be) would need to go through an approval process first, so unnecessary extra costs. That said, it would be nice and more environmentally friendly to have a device where you can just insert your paper strip - but that would totally "give the game away" for everyone to see...

having the strip insertable may make the brightness-assumptions inside the device a bit more muddy. The idea is, that the environment is well-controled. People inserting strips will, over time, put dust on sensors and LEDs. There goes your finely calibrated device and you're in no better situation than the woman outside a well-lit bathroom.

The approval is likely a big issue. The manufacturer can buy the approved strips, and claim that they are validated and accurate. How much paperwork you need to submit for the digital part is an interesting question. I would expect you do need to validate it, but sometimes there are loopholes that allow you to claim it is not a medical device.

Building a phone app to interpret the stripes would be so much less wasteful, but where is the money in that…

Given the beurocratic red tape to creating new medical tests, it's actually a pretty clever solution to just use a few LEDs and a sensor to output a result. I get what people are saying about things but being environmentally friendly, but let's start with our disposable culture towards phones and unnecessary electronics first. Pregnancy tests have a very legitimate and important use

No. How do you know it’s the right test strip? How do you know everything that fits will work correctly?

Simple test and reading them without error are important and life altering. However if have to say I thinks devices like there should be prohibited. To me this is just throwing a lot of e-waste into a problem that is either still not solved or just hidden. By not solved I mean, can't we makes strips that give clearer readings/results? By hidden I mean that if we can't make better pee paper the the device is just hiding ambiguous or unclear result and leaving the user in a false sense of security.

Agree. This feels very much like a "if all you have is a hammer" kind of problem. You could probably create enough energy to get the reading by shaking the test for a few seconds and at least eliminate the battery.

On one page:

https://threadreaderapp.com/thread/1301707401024827392.html

Most (all?) diagnostic medical devices that use simple chemistry will have something that changes colour and an optical reader to detect the colour change.

The predecessor to the ELISA / optical method was the radioimmunoassay (RIA) which used radioactive isotopes instead of optical substrates.

RIAs are still used in some types of tests and also can be set up to test for multiple analytes at the same time.

This made me very depressed. Such a waste on our precious environment. It's like humanity isn't even trying.

For 12 bucks and enough volume sir, they would boil the whole earth like an egg and serve it on a plate.

Women with limited vision surely don’t deserve to know if they’re pregnant. /s

And their coming child deserves to have lower IQ and increased risk of cancer because of heavy metals ending up in the ground water because of batteries in single use items. /s

Properly designed landfills will not leech into the ground water.

I really wonder how many um, people, that buy these tests have been (implicitly) hornswoggled into thinking these gadgets are multiple-use devices. Or that these tests are intrinsically more accurate so will confirm a previous cheaper test.

Deus Ex Silicium as done a few video around these "use once" electronic device

- pregnancy test : https://www.youtube.com/watch?v=iJ8EVFe-0GE

- pregnancy test, the week information : https://www.youtube.com/watch?v=N1x8HnousXg

- Electronic covid test: https://www.youtube.com/watch?v=1nhg9wrcILY

We can't have good things. There are so many products nowadays with pointless embedded disposable electronics that are impossible to recycle. It's absolutely nuts.

What's inside a DIY covid test?

I believe it is to decide the P/NP question :)

Seriously, why isn't there a smartphone app for this or a web service?

Why do you think there's no smartphone app?

Here's one for the iPhones: https://apps.apple.com/us/app/pregnancy-test-checker/id85468...

Here's one for the Androids: https://play.google.com/store/apps/details?id=com.churchdwig...

And if you read some reviews, you can see that the challenge is not trivial.

What a waste of electronic devices. Single use electronics should be declared illegal. I don't get how my country (in EU) bans disposable plastics (and I'm 100% in favor of it) and permits these devices.

I also wonder how many people will dispose this thing properly as electronic waste and how many people will simply throw it in the normal garbage.

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