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Re:Cheap antidepressant shows promise treating early Covid-19 by blinkingled on Wednesday October 27, 2021 @11:47PM (#29022166)
> In the group that took the drug, 11% needed hospitalization or an extended ER stay, compared to 16% of those on dummy pills.

Is that really promising? Very close to margin of error if not within.

Re:Cheap antidepressant shows promise treating early Covid-19 by SkittyDog on Thursday October 28, 2021 @12:07AM (#29022260)
16% > 11% represents a 31% decrease in the absolute number of hospitalizations. That's nearly a ONE THIRD improvement in the hospitalization rate. In places where hospitals are at or near capacity, that would make a huge difference.

Or were you trying to make a statement about the statistical validity of the result, because the outcomes differ by 5%? Because that's not how statistics work. A well constructed study of sufficient size can provide detect arbitrarily small differences in outcomes--you just need a bigger study size, the smaller the difference you want to detect. You would learn about this any 101-level statistics course, and a lot more useful information, too.

Re:Cheap antidepressant shows promise treating early Covid-19 by devwastaken on Thursday October 28, 2021 @01:10AM (#29022596)
Intro to stats says that studies are very difficult and that bias is everywhere. Reinforces how stats can be whatever you want them to be.

Larger Number of people in the sample is a good start. However, bias is also a human element. Therefore you need that study reproduced independently, multiple times.

Researchers don't like this because studies are expensive and hard, and their boss is telling them to publish and get funding. The system is broken.

Re:Cheap antidepressant shows promise treating early Covid-19 by SkittyDog on Thursday October 28, 2021 @02:24AM (#29023014)
For starters, experimental bias isn't really an issue, here... This was an observational study, with crystal clear objective criteria for coding the dependent & independent variables.

A cheap, simple observational study like this is merely a first step. No reasonable expert is claiming that this study proves anything worth making medical policy changes over. This study's sole purpose is to establish whether it's worth investing in further studies, or if we can just shitcan the idea now. Subsequent studies will cost more money, and involve larger samples, better controls, and get a lot more scrutiny from peers.

Time and money are finite resources. You have to have some kind of system for deciding where to spend those resources.

This is how medical science works. It's got a ton of pitfalls, but we still do it this way because so far nobody has come up with a better alternative.

Re:Cheap antidepressant shows promise treating early Covid-19 by thaumasiotes on Thursday October 28, 2021 @02:41AM (#29023100)
> experimental bias isn't really an issue, here... This was an observational study, with crystal clear objective criteria for coding the dependent & independent variables.

I have no position on this particular study, but in general you can make your coding as simple and objective as you like and it won't do much about experimental bias. Objective processing of bad data isn't better than subjective processing of bad data.

This guy wrote a very good essay about data quality: https://desystemize.substack.com/p/desystemize-1

Re:Cheap antidepressant shows promise treating early Covid-19 by SkittyDog on Thursday October 28, 2021 @02:57AM (#29023202)
All studies have some level of risk for bias... But that doesn't mean all studies have the same level of risk.

The essay you linked is very good, but it's actually illustrating my point... The mouse study ran into bias problems because they had to go and directly measure something in nature, and then turn that into a number. That introduces several opportunities for error.

But this SSRI/COVID study isn't doing that. They're literally just looking at patient records, and counting hospitalization vs current SSRI usage. They're not picking up mice to count ticks... They're exporting records to a spreadsheet, and summing columns.

Now, these guys might have problems with the quality of the records they're relying on... Who knows whether the records are accurate or not. But that's a problem of data quality, not experimental bias.

You might say "Who cares? Either kind of error undermines the results, just the same!" But it definitely suggests that the other guy doesn't know what he's talking about... Because if he did understand stats, he would have used the right terminology.

Re:Cheap antidepressant shows promise treating early Covid-19 by thaumasiotes on Thursday October 28, 2021 @06:39PM (#29032944)
> The essay you linked is very good, but it's actually illustrating my point... The mouse study ran into bias problems because they had to go and directly measure something in nature, and then turn that into a number. That introduces several opportunities for error.

> But this SSRI/COVID study isn't doing that. They're literally just looking at patient records, and counting hospitalization vs current SSRI usage. They're not picking up mice to count ticks... They're exporting records to a spreadsheet, and summing columns.

> Now, these guys might have problems with the quality of the records they're relying on... Who knows whether the records are accurate or not. But that's a problem of data quality, not experimental bias.

Well, no, I have to disagree with this analysis. The mouse study described in that essay didn't run into bias problems, and the reason it didn't is that it was counting the ticks itself. But other tick-counting studies did have bias problems (due to bad methodology), and the Lyme-disease studies based on the bad tick-counting studies had the same bias problems (because they were using the bad data). The bias doesn't go away when you wash it through two publications instead of one. It's not a different kind of problem -- or even a different instance of the same kind of problem! -- and there's no reason to give it a different name.

Re:Cheap antidepressant shows promise treating early Covid-19 by jimbojet on Thursday October 28, 2021 @03:24AM (#29023364)
You sound like you just took a stats 101 class and now are bragging to a bunch of adults about how much you learned in stats 101. Sincerely, someone working in the field for last 7 years.
Re:Cheap antidepressant shows promise treating early Covid-19 by SkittyDog on Thursday October 28, 2021 @03:46AM (#29023477)
Sounds like I don't know nearly as as you... I minored in stats 20+ years ago, but since then I do a lot more arguing about stats than actually using them for work.

You're kinda right about one thing, though... I am definitely talking down to OP, and a couple of other folks.

I'm frustrated. There are real problems in how science uses statistics, and it sounds like OP & co have heard about those problems. But the way they talk about this study, they're just throwing crap against the wall to have something to say. They don't really seem to understand the problems they're talking about, or how those problems apply to the study we're currently talking about.

I should change my attitude, and stop taking out my frustrations on these folks. If they're wrong, I'm probably not going to change their minds by insulting them.

Re:Cheap antidepressant shows promise treating early Covid-19 by ordu on Thursday October 28, 2021 @06:55AM (#29024538)
> For starters, experimental bias isn't really an issue, here... This was an observational study, with crystal clear objective criteria for coding the dependent & independent variables.

Just a nitpick: it was not an observational study, it was a true experiment, because they controlled the treatment: it was assigned by researchers at random. It is by definition not an observational study which have a distinctive feature that it doesn't control for a treatment.

Re:Cheap antidepressant shows promise treating early Covid-19 by darkerside on Thursday October 28, 2021 @12:32AM (#29022409)
N = 1500

One sample had 79-86 out of 750 hospitalized, and the other had 117-123 out of 750.

Does that seem sufficient to demonstrate statistical significance?

Edit: found the actual numbers in the study

79 [11%] of 741 vs 119 [16%] of 756

Re:Cheap antidepressant shows promise treating early Covid-19 by _3u10 on Thursday October 28, 2021 @01:01AM (#29022554)
I ran it through an AB test significance calculator using the upper bound for each.

p value was 0.9972 and the power was 92.40% it's a significant result.

"Variant B’s conversion rate (11.47%) was 30.08% lower than variant A’s conversion rate (16.40%). You can be 99% confident that variant B will perform worse than variant A."

Re:Cheap antidepressant shows promise treating early Covid-19 by Jabbles on Thursday October 28, 2021 @06:22AM (#29024302)
You can be 99% confident

To be more precise without being too formal:

If there truly were no difference between them, you could be 99% confident that you would not get a result like this.

Re:Cheap antidepressant shows promise treating early Covid-19 by darkerside on Thursday October 28, 2021 @01:03AM (#29022563)
> When the DSMC met on Aug 5, 2021, it recommended that the TOGETHER trial stop randomly assigning patients to the fluvoxamine group, as this comparison had met the prespecified superiority criterion for the primary endpoint (prespecified superiority threshold 97·6%).

That seems problematic. Did they stop the study because they had achieved statistical significance?

Re:Cheap antidepressant shows promise treating early Covid-19 by scarmig on Thursday October 28, 2021 @01:28AM (#29022700)
Another issue is that they were testing multiple drugs, none of which had a statistically significant effect. Classic p hacking.

https://xkcd.com/882/

Re:Cheap antidepressant shows promise treating early Covid-19 by scotty79 on Thursday October 28, 2021 @05:24AM (#29024019)
Assesing 7 promising substances to determine which one if any does anything and getting 30% effect on one and no effect on the rest is p-hacking?

Is science allowed to research only one substance for specific purpose at any time to sufficiently avoid p-hacking for you?

Also if I read correctly they got >0.60 not >0.05

Re:Cheap antidepressant shows promise treating early Covid-19 by SkittyDog on Thursday October 28, 2021 @12:37AM (#29022426)
Yes, as a matter of fact, it does demonstrate statistical significance.
Re:Cheap antidepressant shows promise treating early Covid-19 by darkerside on Thursday October 28, 2021 @12:39AM (#29022442)
For what minimum detectable effect?
Re:Cheap antidepressant shows promise treating early Covid-19 by goldemerald on Thursday October 28, 2021 @01:56AM (#29022855)
You'd be interested in learning about the origin and application of Chi-Squared tests (or Fisher's exact test). Detecting changes in population means, and making sure those changes aren't just random noise, is quite straightforward and can be done by hand.
Re:Cheap antidepressant shows promise treating early Covid-19 by SkittyDog on Thursday October 28, 2021 @02:07AM (#29022910)
It won't be possible for me to explain the answer to your satisfaction, if you lack at least a basic education in probability & statistics. Maybe Khan Academy has an intro level course, or a "Stats for Humanities" variant that can help you get started.
Re:Cheap antidepressant shows promise treating early Covid-19 by novaRom on Thursday October 28, 2021 @01:31AM (#29022707)
I wish every news media to show original numbers always, not percentage.
Re:Cheap antidepressant shows promise treating early Covid-19 by ekianjo on Thursday October 28, 2021 @12:53AM (#29022515)
Most drugs get approved with less strong effect than this
Re:Cheap antidepressant shows promise treating early Covid-19 by darkerside on Thursday October 28, 2021 @12:58AM (#29022538)
Well, of course they do. There's a terrific market for pharmaceuticals.
Re:Cheap antidepressant shows promise treating early Covid-19 by s5300 on Thursday October 28, 2021 @12:12AM (#29022294)
IMO, one of the largest hurdles that modern society is going to have to overcome is the average person's understanding of large (or small) numbers and basic statistics.

I think a large issue within that hurdle is that a lot of people simply won't want to learn, or apply the knowledge after learning.

Re:Cheap antidepressant shows promise treating early Covid-19 by SkittyDog on Thursday October 28, 2021 @12:28AM (#29022393)
And the funny thing is that the original commenter was looking at a trivial math problem. It wasn't even a question of statistical validity, it was just "What does it mean to compare percentages to each other?" That's grade-school mathematics.

I see this kind of error pretty frequently, and it's usually not a failure of mathematics... Most often, the person has some pre-existing negative emotional reaction to the stated conclusion, and their brain searches for something to criticize, in order to soothe those negative emotions.

I could only speculate as to why the original poster doesn't like hearing that an existing drug shows promise in treating COVID. Maybe they're a big Ivermectin booster, and they don't like the idea of another drug threatening their favorite?

Re:Cheap antidepressant shows promise treating early Covid-19 by matjet on Thursday October 28, 2021 @01:34AM (#29022730)
I think you might want to reconsider your opinion of others. I believe the OP was referring to this result being on the edge of statistical significance given: The effect size relative to the base population; The fact that many similar trials are performed and discarded with similar drugs; And as we see when looking deeper, there are other issues such as early stopping. It is not unreasonable to suspect the effect could disappear given more data.
Re:Cheap antidepressant shows promise treating early Covid-19 by SkittyDog on Thursday October 28, 2021 @02:36AM (#29023070)
YOU are raising some valid points... but based on the OP's other comments, they seem to have a very limited knowledge of statistics--and yet, they are pushing a very critical line on this topic.

OP is asking other posters to do quite a bit of homework for them... As in, "Is this study big enough?" <<YES>> "OK, but how big does it need to be to prove X?" ... At a certain point, it seems clear that OP is not arguing in good faith, because they feel compelled to make the critical statements, first, without understanding the topix.

I would caution you to not extend sympathy to OP's cause, simply because you happen to share a critical eye for this study. There is a HUGE difference between being right for the right reason, vs the wrong reason... and that's how we get crap like Ivermectin for COVID.

Re:Cheap antidepressant shows promise treating early Covid-19 by chmod600 on Thursday October 28, 2021 @12:33AM (#29022416)
I don't know what the other post had in mind, but does seem like smaller effect sizes have a way of evaporating under scrutiny.

One third is pretty big when looking at it from a group perspective, but not really that big from a personal perspective.

If someone told me that taking a pill would reduce my chances of hospitalization by 5%, I would certainly be looking closely at the side effects.

Re:Cheap antidepressant shows promise treating early Covid-19 by rscho on Thursday October 28, 2021 @12:51AM (#29022505)
5% is not a pointwise prediction at the individual level. You can't interpret it like you did.
Re:Cheap antidepressant shows promise treating early Covid-19 by fallingknife on Thursday October 28, 2021 @01:28AM (#29022701)
In a way it is though. There is a 84% chance you wouldn't go to the hospital either way, an 11% chance that you will go to the hospital either way, and a 5% chance that you will be saved from going to the hospital. So there is a 1 in 20 chance that this drug will save you from being hospitalized. It could also make your illness less severe in the other scenarios though.
Re:Cheap antidepressant shows promise treating early Covid-19 by npunt on Thursday October 28, 2021 @02:06AM (#29022901)
Population and individual stats are different though. If someone is older and in a higher risk group, the drug could indeed reduce hospitalization risk for that individual much more than 5%, while for other low-risk groups it could do next to nothing.
Re:Cheap antidepressant shows promise treating early Covid-19 by rscho on Thursday October 28, 2021 @05:37AM (#29024062)
No, sorry...
Re:Cheap antidepressant shows promise treating early Covid-19 by blinkingled on Thursday October 28, 2021 @06:51AM (#29024500)
Well thank you for stats 101 but what I was trying to ask was that if this level of confidence promising within medical/pharma field - i.e. do we have stats on studies that said something like out of the 767 or whatever studies that claimed a drug sounded promising because it was associated with 5% outcome improvement - 90% resulted in long term commercial success of the drug.

I mean take Remdesivir - https://www.nejm.org/doi/full/10.1056/nejmoa2007764 - statistically significant yet some other studies found it had no benefits. At least I don't think it was a slam dunk or promising in real life as day the vaccines.

Re:Cheap antidepressant shows promise treating early Covid-19 by SkittyDog on Thursday October 28, 2021 @04:53PM (#29031843)
It sounds like you're asking "What's the risk that this study will turn out to be wrong, in the long run?" That's a very interesting question, but sadly there's no way to answer it from the available data.

Different studies can show different results for a lot of reasons... Sometimes, it's just random chance. Other times, it's due to bad study design, or poor experimental controls, or deliberate P-hacking. There's no way to tell from the results of a single study.

But that's not what this study is for, anyway... This is a preliminary observational study to look for possible drug candidates that might impact COVID severity. It's only suggesting potential future directions of investigation, not advocating for immediately dosing everyone with SSRIs... Medical policy changes won't happen until a much larger body of evidence has been established.

It's the nature of science that not all experiments produce correct results. Sometimes, we get it wrong--but that's why we have to keep repeating experiments, and trying different variations, before we trust a conclusion.

In the meantime, though, medical decision makers will weigh the costs vs benefits of proceeding with an experimental treatment... If the risks are low, and the need is great, they'll probably let the door open to more experiments. Most people seem to think that's a pretty sensible way to do things.

Re:Cheap antidepressant shows promise treating early Covid-19 by ekianjo on Thursday October 28, 2021 @12:55AM (#29022525)
Margin of error is not fixed. Depends on sample size. if you have a group of millions your error range will be in the hundredth of a percent. Here we are not talking about 20 people in each group. 1500. Thats very significant.

I recommend you take some stats courses if this does not make sense.

Re:Cheap antidepressant shows promise treating early Covid-19 by pertymcpert on Thursday October 28, 2021 @12:01AM (#29022225)
> The results, published Wednesday in the journal Lancet Global Health, were so strong that independent experts monitoring the study recommended stopping it early because the results were clear.
Re:Cheap antidepressant shows promise treating early Covid-19 by nottorp on Thursday October 28, 2021 @05:09AM (#29023954)
I'd like some info about those "independent experts".
Re:Cheap antidepressant shows promise treating early Covid-19 by tinus_hn on Thursday October 28, 2021 @07:18AM (#29024698)
Yeah, I only trust experts employed by the manufacturers of new, expensive, patented medication with severely limited availability!
Re:Cheap antidepressant shows promise treating early Covid-19 by nottorp on Thursday October 28, 2021 @07:29AM (#29024780)
I only trust experts that are specified, not nebulous "independent experts" :)
Re:Cheap antidepressant shows promise treating early Covid-19 by darkerside on Thursday October 28, 2021 @12:50AM (#29022494)
> When the DSMC met on Aug 5, 2021, it recommended that the TOGETHER trial stop randomly assigning patients to the fluvoxamine group, as this comparison had met the prespecified superiority criterion for the primary endpoint (prespecified superiority threshold 97·6%).

This... is not how it's supposed to work.

Re:Cheap antidepressant shows promise treating early Covid-19 by npunt on Thursday October 28, 2021 @02:14AM (#29022944)
Actually, it is. This is an adaptive clinical trial, meaning its part of the protocol to change when pre-set criteria are met. This is stated in the paper. There's a whole body of work on the ethics and statistics of adaptive clinical trials and when to stop them early if promising results are found.

https://en.wikipedia.org/wiki/Adaptive_clinical_trial

Re:Cheap antidepressant shows promise treating early Covid-19 by darkerside on Thursday October 28, 2021 @08:25AM (#29025230)
https://academic.oup.com/jnci/article/104/18/1347/924103

> He also cautioned against “play the winner” designs that increase the number of patients being randomized to arms that show the best results in an interim analysis. “That is most often used in early phase trials, like a Phase I or early Phase II trial where you’re really trying to identify the best dose level; such trials tolerate bias pretty well,” Sietsema said. “But you wouldn’t use a play- the-winner model in a Phase III trial because the potential for bias could lead to a wrong decision and the FDA would object.”

That sums up my concerns pretty well. This is being presented as a phase III clinical trial demonstrating safety and efficacy. For the level of effect they are testing for, I don't see how an adaptive trial is appropriate here.

Re:Cheap antidepressant shows promise treating early Covid-19 by _3u10 on Thursday October 28, 2021 @01:06AM (#29022577)
Perhaps they were more interested in saving people's lives than waiting for the trial to conclude... I mean the downside is people are less depressed while on a ventilator.
Re:Cheap antidepressant shows promise treating early Covid-19 by nuerow on Thursday October 28, 2021 @03:27AM (#29023386)
> Perhaps they were more interested in saving people's lives than waiting for the trial to conclude...

The bit "waiting for the trial to conclude" actually means "determine if the drug actually has any effect or not".

No matter how much you are interested in saving people's lives, or any other moralistic fallacy that might pop up, you can only help them if you give them treatments that actually work. Cutting short a study is falling short of the most basic requirement to meet that goal.

Re:Cheap antidepressant shows promise treating early Covid-19 by scotty79 on Thursday October 28, 2021 @05:38AM (#29024067)
The point is that math shows they determined that it has an effect before the trial ended.

So now you are faced with a conundrum. You made sure that it has an effect to the degree you wanted. Now the math says that you either might get even surer by continuing the trial, or save 30% people from hospitalisation.

Also in treatment group just one person died while in control it was 12.

So what's it going to be? Making little bit more sure or saving few lives?

Re:Cheap antidepressant shows promise treating early Covid-19 by nuerow on Thursday October 28, 2021 @06:12AM (#29024252)
> The point is that math shows they determined that it has an effect before the trial ended.

With a small enough sample, math can show that a coin flip gives tails 4 out of 5 times, specially if it's stopped too soon.

Don't you agree that stopping an experiment once we get the result we were hoping for and are looking for from the start does raise doubts regarding the conclusion?

Re:Cheap antidepressant shows promise treating early Covid-19 by scotty79 on Thursday October 28, 2021 @06:30AM (#29024355)
With small enough sample math tells you exaclty how little confidence can you have in a given result.

And for a group of 1500 people it tells you how much confidence can you have. And it was more confidence than they demanded before starting the trial.

> Don't you agree that stopping an experiment once we get the result we were hoping for and are looking for from the start does raise doubts regarding the conclusion?

If you have a novel disease that's 99% fatal. And then you test a treatment that results in 30% people surviving 99% fatal disease. And you gathered enough data that that math tells you is enough to confidently claim that it isn't just a fluke.

Does stopping the trial and giving the medicine to the half of patients that you were keeping as a control group makes people raise doubts about efficacy of the drug or does that just make you not be called a second doctor Mengele?

Did they stop fluvoxamine trial? Or do they just mention that the effect was so strong that they could?

Re:Cheap antidepressant shows promise treating early Covid-19 by ARandomerDude on Thursday October 28, 2021 @01:15AM (#29022624)
No. It's called p-hacking, and it's a sleazy way to get published.

https://youtu.be/42QuXLucH3Q

Re:Cheap antidepressant shows promise treating early Covid-19 by bpodgursky on Thursday October 28, 2021 @01:58AM (#29022865)
This is not p-hacking. p-hacking is when you don't pre-register your hypothesis and you hunt for ones which hit .05 after the fact.

There was a single hypothesis being tested here.

Re:Cheap antidepressant shows promise treating early Covid-19 by darkerside on Thursday October 28, 2021 @01:03PM (#29028339)
It was an adaptive clinical trial with multiple arms, so it wasn't a single hypothesis. Apparently this is considered legitimate in medical trials, but I have some reservations about the concept.
Re:Cheap antidepressant shows promise treating early Covid-19 by scotty79 on Thursday October 28, 2021 @05:42AM (#29024083)
Also this was >0.60 not around 0.05 If I read correctly.
Re:Cheap antidepressant shows promise treating early Covid-19 by bpodgursky on Thursday October 28, 2021 @01:57AM (#29022859)
This is not uncommon or wrong.
Re:Cheap antidepressant shows promise treating early Covid-19 by darkerside on Thursday October 28, 2021 @12:35AM (#29022424)
This sounds suspiciously vague. What experts? How did they become involved? Did they stop it because the study proved an effect, or because it was clearly not designed to be able to prove an effect?
Re:Cheap antidepressant shows promise treating early Covid-19 by _3u10 on Thursday October 28, 2021 @01:08AM (#29022584)
How does your ad hominem questioning of their expertise / how they became involved invalidate the results?

The study reached its statistical significance goal, and thus the study was ended as it would be immoral beyond that point to continue to give people placebos when they knew the drug was working. I'd suggest reading up on the Tuskegee syphilis study for the ethics behind why studies are ended early once treatments have been statistically validated.

Re:Cheap antidepressant shows promise treating early Covid-19 by rtpg on Thursday October 28, 2021 @12:06AM (#29022253)
Dunno about the sample size, but sounds like "1/3rd of hospitalizations prevented" to me.

Though it's like... isn't the vaccine in the initial phases like "80+% of hospitalizations prevented"? I guess it's good to have all these options but would be nice to just get good vaccine coverage.

Re:Cheap antidepressant shows promise treating early Covid-19 by z80x86 on Thursday October 28, 2021 @12:28AM (#29022390)
> A cheap antidepressant reduced the need for hospitalization among high-risk adults with COVID-19 in a study hunting for existing drugs that could be repurposed to treat coronavirus.

You’re right to be suspicious; data dredging 101.

Re:Cheap antidepressant shows promise treating early Covid-19 by shapefrog on Thursday October 28, 2021 @04:31AM (#29023727)
Astham went from being a risk factor to a risk reduction factor. Smoking likewise, we are even at the point where One study suggests this could be because nicotine interferes with ACE2 receptors, which may prevent the virus from entering cells.

Why isnt everyone having a cigarette each day to interfere with the ACE2 receptors?

Re:Cheap antidepressant shows promise treating early Covid-19 by ekianjo on Thursday October 28, 2021 @12:52AM (#29022514)
Effect size.
Re:Cheap antidepressant shows promise treating early Covid-19 by bellyfullofbac on Thursday October 28, 2021 @12:50AM (#29022497)
Hah, backseat statistician are we? The next sentence of the article that said experts recommended to end the trials early should make it clear to you that to them that's really promising. Your last sentence basically says you're sure you know better than the panel of experts.

I don't know what the point of my reply is other than to recommend to you to have some humility that you might not know stuff...