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Curry spice turmeric boosts memory by nearly 30%, eases depression, study finds

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Re: Curry spice turmeric boosts memory by nearly 30%, eases depression, study finds

#341

Post by yufeng66 »

andrewjl wrote: post #232
sov wrote: post #220

Earlier quoted context omitted.

> Small study Almost entirely irrelevant, provided it's properly powered--and based on the effect size and p-values, it is. Furthermore, for an 18 month trial, 40 people is larger than most. > probably not preregistered I mean, true, and we should definitely promote pre-reg, but, 1. so few are preregistered that I'm not sure it's prudent to disregard a study based on this and 2. it's an academic study, neither a clin…

What prevents researchers from running studies like these on the order of thousands of individuals, as opposed to 40 or 100?

As others have pointed out. Its about money. If the compound is expected to be very profitable, then it make sense to invest a lot money to do a large scale study. On the other hand, if it is a natural compound that you can't really patent, the profitability will be much lower. It doesn't make sense for a commercial entity to do a large scale study. If the compound is important enough, a government entity will sometimes invest the money to study it.

Re: Curry spice turmeric boosts memory by nearly 30%, eases depression, study finds

#342

Post by closed »

vanderZwan wrote: post #330
closed wrote: post #323

Earlier quoted context omitted.

When a small sample size produces a big effect, it does not mean you can be more confident in the effect! All things equal, you'd expect confidence intervals / credible regions to be very large. Another way to say this, is that since the measurement error is large, you expect spurious findings that result from something like p-hacking to be large (they have to be to be significant).

What annoys me as a someone not trained in statistics is that these discussions are always abstract in-principle arguments about what proper statistics should be like. Meanwhile, we have a real paper with real p-values , why not discuss the validity of that? > SRT Consistent Long-Term Retrieval improved with curcumin (ES = 0.63, p = 0.002) but not with placebo (ES = 0.06, p = 0.8; between-group: ES = 0.68, p = 0.05).…

I agree with the other commenter, and Gelman's blog is a good place to start. There are very clear, concrete statistical arguments, but they are difficult to summarize in the comments section of HN.

The gist is like this. Imagine that someone had people play 20 different slot machines. Then they went into a private room and looked at the results for each machine. After, they come out with the results of 5 of the machines and say, "look, our slot machines pay out at a higher than chance level!".

Do you believe them? I hope not. If only 4 machines had done well, maybe they would have shown only 4, or 3, etc.. They've effectively stacked the deck.

On the other hand, suppose someone said they were running an honest experiment with 20 slot machines. How many machines would you expect them to report on?

Re: Curry spice turmeric boosts memory by nearly 30%, eases depression, study finds

#343

Post by pbhjpbhj »

e12e wrote: post #262
andrewjl wrote: post #232

Earlier quoted context omitted.

What prevents researchers from running studies like these on the order of thousands of individuals, as opposed to 40 or 100?

If they're marketing their own drug (as implied by other comments - I don't know), you might also ask what stops them from running the studio on a 100 groups of 40 patients, and picking the "best" for publication... (other than ethics, obviously)...

Cheaper to run it on 100 and select the best 40 to report in your study.

Re: Curry spice turmeric boosts memory by nearly 30%, eases depression, study finds

#344

Post by pbhjpbhj »

dumbneurologist wrote: post #305
hannob wrote: post #152

Small study, probably not preregistered (didn't find anything about it in the description). Likely Publication Bias or p-hacking. I'm starting to get interested when it's been independently replicated.

agree that replication is important and that it's too early to believe fully, but when a study size is small and you still find a difference, then it implies the effect size is large. If you meet statistical significance, then diminishing n means increasing clinical significance.

I flipped 5 coins, 4 came up heads, so heads must be >>80% likelihood??

Re: Curry spice turmeric boosts memory by nearly 30%, eases depression, study finds

#345

Post by soVeryTired »

dumbneurologist wrote: post #306
pjmorris wrote: post #150

Earlier quoted context omitted.

I am having trouble accepting your argument. Judea Pearl presents [0] the debate over whether smoking causes cancer as an illustration for why correlation is not sufficient. Two plausible, contradictory, models ('smoking causes cancer', 'no it doesn't, something else does') could not be settled by observing correlations. The debate was resolved through the addition of an explanatory mechanism, and a test of the mecha…

none of this applies to a double-blind, placebo-controlled, randomized clinical trial (which is what this article is). the reason it's the gold standard for medicine is because the only thing that is different in aggregate between the groups is the intervention. Therefore, it is the strongest possible evidence of causality we have, and does say something about causality (rather than correlation). It's important to re…

Andrew Gelman has a nice blog post on the shortcomings of the double blind clinical trial:

http://andrewgelman.com/2018/01/08/benefits-limitations-rand...

To be honest, I think a randomised clinical trial is more of a starting point than an endpoint in terms of 'knowing' that an effect is genuine. The 'gold standard' moniker overdoes the authority of the RCT a

Re: Curry spice turmeric boosts memory by nearly 30%, eases depression, study finds

#346

Post by pbhjpbhj »

jjgreen wrote: post #294
jeffdavis wrote: post #206

Earlier quoted context omitted.

I somewhat agree, but "is it true?" is all that science can answer. A mechanism is really just a narrower example without irrelevant distractions or confounding variables. Kind of like the difference between the bug reports: "run this complex workload on this specific machine and it will orobably crash after a few hours" versus "run these three commands when the cache is cold and it crashes".

I find it odd that the sibling reply by fleitz (all that science can say is "is it false"), which just a precis of Popperian philosophy of science, has been marked dead. Not a view that I share, but seems uncontroversial.

Agreed, indeed my immediate response to that comment was "that's not how science works, it's falsificationist".

What is your view on science, do you think it can create - and verify - a true result? Whither axiomatic underpinning in such a view?

Re: Curry spice turmeric boosts memory by nearly 30%, eases depression, study finds

#347

Post by WalterSear »

wavegeek wrote: post #204
zaptheimpaler wrote: post #195

Earlier quoted context omitted.

Obviously you don't understand HN.. everyone here is a "very smart software engineer" and knows far better than a simpleton like you with your decades of medical training and experience.

> decades of medical training and experience http://slatestarcodex.com/2013/12/17/statistical-literacy-am... Ask your local doctor next time you visit to tell you what a P value means. The medical literature is a tragicomedy of statistical incompetence and malpractice. Specifically on this study it has a lot of red flags: not pre-registered so p hacking can be assumed, industry sponsored which studies show greatly sk…

It was pre-registered. However, they did a battery of tests, and only report on a few. This is a method of cheating on the pre-registry process.

Re: Curry spice turmeric boosts memory by nearly 30%, eases depression, study finds

#348

Post by dboreham »

danielvinson wrote: post #168
dboreham wrote: post #125

Earlier quoted context omitted.

That papaya might not be safe though.

Why wouldn't a papaya be safe? Everything I've seen says that the seeds are always edible.

Ironic comment : Drug companies tell us we can't buy their products through other countries (at much lower cost) because "safety".

Re: Curry spice turmeric boosts memory by nearly 30%, eases depression, study finds

#349

Post by rbanffy »

Flow wrote: post #266
maxxxxx wrote: post #203

Earlier quoted context omitted.

Turmeric has helped me quite a bit with my inflamed joints after learning about it at a yoga ashram. Now I cook a lot with it. What i have noticed though is that supplements do nothing for me. I only feel a difference when it's fresh powder or even better ground from a root. I have done several experiments where I stopped taking it. Every time my joints got worse and then better after resuming cooking with Turmeric.…

It common among men with low testosterone to have aching joints. Have you checked your levels? Also funny that some men on TRT take turmeric(with some black pepper) to lessen the amount of estrogen converted from testosterone.

> It common among men with low testosterone to have aching joints.

Great... We can have either pain or hair loss... And don't even think about the prostate...

Intelligent design... Meh...

Re: Curry spice turmeric boosts memory by nearly 30%, eases depression, study finds

#350

Post by vanderZwan »

closed wrote: post #342
vanderZwan wrote: post #330

Earlier quoted context omitted.

What annoys me as a someone not trained in statistics is that these discussions are always abstract in-principle arguments about what proper statistics should be like. Meanwhile, we have a real paper with real p-values , why not discuss the validity of that? > SRT Consistent Long-Term Retrieval improved with curcumin (ES = 0.63, p = 0.002) but not with placebo (ES = 0.06, p = 0.8; between-group: ES = 0.68, p = 0.05).…

I agree with the other commenter, and Gelman's blog is a good place to start. There are very clear, concrete statistical arguments, but they are difficult to summarize in the comments section of HN. The gist is like this. Imagine that someone had people play 20 different slot machines. Then they went into a private room and looked at the results for each machine. After, they come out with the results of 5 of the mach…

I can follow your analogy, but it doesn't quite add up.

The researchers took a group of people and submitted each of them to an "extensive neuropsychologist test battery".

That's not just testing 20 different slot machines, that's testing 20 different designs of slot machines.

(Also, each person does each test on their own, which is the equivalent of having them not only play twenty different models, but a unique production per person unit per model)

In that light, the claim that all slot machines have a high pay-out chance is obviously suspicious, but would coming back and saying "these five designs have a higher than chance level of winning!" be an incorrect conclusion?

If each slot machine types is unique, no. But if one slot machine design is known to have a flaw, and if it shares this flaw with another design, and if that other design does not show the same increased performance, then things get really suspicious.

So the question becomes: do we know how strongly correlated the results of these tests typically are? If that is a lot (which I would expect to be true with at least some of these tests), the absence of the other tests is suspicious. If it is low, it might be less of an issue.

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