Search Results for "effect decline"

Jun 02 2011

The Decline Effect Revisited

I have written previously about the decline effect – the apparent decrease in the magnitude of a phenomenon as it is scientifically studied. Initially there seems to be a big effect, but the effect size shrinks as further research is done, sometimes shrinking all the way to zero.

This effect was perhaps first observed (or at least named) in psi research. Over the last century psi researchers have come up with a number of research paradigms to demonstrate so-called anomalous cognition. But in every case the initial impressive effect sizes have shrunk to non-existence with repetition. While the standard interpretation of this failure to reproduce results is that the phenomenon is not real, some defenders of psi have tried to argue there is a real metaphysical decline effect at work. It’s not their fault – the phenomenon actually goes away over time.

Writing for Naturenews, Jonathan Schooler makes a similar claim about the interpretation of the decline effect in science in general. To be fair, this is not the focus of his article. He is making an argument for registering all scientific studies, so that publication bias cannot distort the patterns of evidence in the literature. I completely agree. But within his article he writes:

Perhaps, just as the act of observation has been suggested to affect quantum measurements, scientific observation could subtly change some scientific effects. Although the laws of reality are usually understood to be immutable, some physicists, including Paul Davies, director of the BEYOND: Center for Fundamental Concepts in Science at Arizona State University in Tempe, have observed that this should be considered an assumption, not a foregone conclusion.

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Dec 13 2010

The Decline Effect

While there is a complex spectrum of attitudes toward science, there are three clusters worth pointing out, specifically in reference to the provocative New Yorker article by Jonah Lehrer called The Truth Wears Off. The first group are those with an overly simplistic or naive sense of how science functions. This is a view of science similar to those films created in the 1950s and meant to be watched by students, with the jaunty music playing in the background. This view generally respects science, but has a significant underappreciation for the flaws and complexity of science as a human endeavor. Those with this view are easily scandalized by revelations of the messiness of science.

The second cluster is what I would call scientific skepticism – which combines a respect for science and empiricism as a method (really “the” method) for understanding the natural world, with a deep appreciation for all the myriad ways in which the endeavor of science can go wrong. Scientific skeptics, in fact, seek to formally understand the process of science as a human endeavor with all its flaws. It is therefore often skeptics pointing out phenomena such as publication bias, the placebo effect, the need for rigorous controls and blinding, and the many vagaries of statistical analysis. But at the end of the day, as complex and messy the process of science is, a reliable picture of reality is slowly ground out.

The third group, often frustrating to scientific skeptics, are the science-deniers (for lack of a better term). They may take a postmodernist approach to science – science is just one narrative with no special relationship to the truth. Whatever you call it, what the science-deniers in essence do is describe all of the features of science that the skeptics do (sometimes annoyingly pretending that they are pointing these features out to skeptics) but then come to a different conclusion at the end – that science (essentially) does not work.

I often feel that those in this third group – the science deniers – started out in the naive group, and then were so scandalized by the realization that science is a messy human endeavor that the leap right to the nihilistic conclusion that science must therefore be bunk.

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Mar 06 2023

A Climate Debate Regarding Health Effects – Part III

Published by under General Science

Part 3

Hi Steve, and thank you for your timely response, and for even considering hosting this debate. There has been, and continues to be a “blackout” on almost all discussion regarding the science behind climate change. If “The science” is truly “settled”, it is a pretty shaky settlement! Why the blackout then?

I appreciate that you have pointed out some of my quirks that I use in constructing and argument. After all, this is a debate, and of course we come at it with different viewpoints and narratives, which makes debates all the more profoundly important to have. I think we would all agree that listening to other viewpoints other than our own, although may be uncomfortable, nonetheless helps us become more intelligent, enlightened, and wise.

While I do appreciate the pointing out of my biases (which we all have), there was very little substantive rebutting of the information I provided. I did use exact verbiage from the latest IPCC report, so nobody could accuse me of making a strawman argument. If you think I’m setting up a bunch of strawman arguments, I invite you to reach out to the authors of IPCC chapter 11: Human Health: Impacts, Adaptation, and Co-benefits and ask them why they are setting up these supposed confounded strawman arguments for me. If I can’t quote IPCC, the most trusted source of climate change information, then who can anyone trust regarding climate change information? The words I used to base my argument upon are their words, not mine. 

You state: “So Scott’s method is fatally flawed – you cannot just look at raw incidence numbers and declare there is no effect from climate change…But Scott dismisses all of this as “modeling”, which he rejects out of hand, explicitly favoring raw data, which is profoundly naive. He also dismissed data on the risks increased by climate change, again favoring raw data that mixes in many confounding variables.”

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Feb 27 2023

A Climate Debate Regarding Health Effects – Part I

This is the first entry in an exchange between me and Scott Hastings, who requested the exchange. This is his opening arguments. My response will be tomorrow’s post.

 

Part I:

Hi Steven, first of all, I am tremendously grateful to you for taking time to engage with me on this very important topic. Thank you.

I’d like to start by sharing just a few media articles I found that are now over 3 years old:

New York Times: November 13, 2019 “Climate Change Poses Threats to Children’s Health Worldwide

ABC News Australia: November 5, 2019 “11,000 scientists declare climate emergency warning world faces catastrophic threat

CNN: November 12, 2019 “The climate crisis will profoundly affect the health of every child alive today,

Wired: November 13, 2019 “How the Climate Crisis Is Killing Us, in 9 Alarming Charts, A new report from over 100 experts paints a devastating picture of how climate change is already imperiling human health.”

We are both physicians, so I don’t want to leave out the American Medical Association statement on climate change.

I think you get the point…We are daily inundated with a “climate emergency” just around the corner.  It also seems that all the experts (at least 97% anyway) are in some general agreement about the “devastating catastrophe” lurking somewhere out there. However, the official IPCC-5 report seems to be a whole lot less confident than the headlines mentioned above.

My aim is to take exact verbiage from IPCC-5, then apply the most up to date scientific literature available to cross-check their stated claims. Since I’m a physician, I am specifically interested in health outcomes as a result of climate change. I am looking at global health trends (since this is a global phenomena), as well as trends in global natural events like floods, fires, and hurricanes as these obviously contribute to health outcomes.  It’s simple really, in our world of experts, nobody needs to be an expert at opening the newspaper the morning after the superbowl to see who won the game. In this case, the “newspaper” is going to be scientific research literature based on global observational trends from generally that was published in the past 6 years. What I will not include is modeling studies. That’s like trying to predict who is going to win the superbowl. I’m not interested in that.  Just real-world objective observations found on google scholar or pubmed. I’m only interested in who won the superbowl, not in some supposed “superbowl prediction expert”.

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Dec 11 2018

Study – Mental Activity Does Not Prevent Decline

Published by under Neuroscience

There has been a very interesting debate going on in neuroscience over the impact of so-called “brain training” activities and cognitive ability and decline. No one study, of course, is ever going to be the final word on this debate, but a new study does add one more piece to the puzzle. Unfortunately it shows that increased mental engagement (doing puzzles, engaging in problem solving, etc.) does not alter the course of mental decline in later years.

But let’s back up and frame the question a bit more. The overarching question is – what is the effect on the brain and on cognitive ability from engaging in various kinds of mental activity? A cottage industry has risen out of one extreme end of opinion on this question, the notion that certain kinds of mental activity could have wide ranging benefits. This is the “brain training” claim – doing specially designed puzzles will make you smarter, and maybe even prevent dementia.

Although Lumosity often gets cited for making these claims, I think it started much earlier, in the 1990’s with the Baby Mozart movement. In 1993 a short paper was published in Nature, involving a small number of college students who were either exposed to classical music or just relaxation. They were then tested with a paper folding task, and those who listened to the music did a litter better. This was a small preliminary study in college students showing a very narrow effect. Yet somehow this tiny and insignificant paper was used to create the myth of the so-called “Mozart effect” – that children who are exposed to classical music will become generally smarter.

Later studies showed no such effect, but the genie was out of the bottle. A cottage industry of “Baby Mozart” and “Baby Einstein” (because, why not?) products still thrive to this day. This spawned a more general claim that mental activity can “train your brain” to make you generally smarter.

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Aug 13 2013

Mefloquine and Psychiatric Side Effects

On a recent episode of The Newsroom one reporter was headed to Africa and was advised by a more senior producer not to take mefloquine for malaria prophylaxis because of the potentially severe psychiatric side effects. I had never heard that before, never having traveled to a malaria area, and malaria prophylaxis being outside my area of medical expertise.

Then I was sent a link to a recent New York Times article called Crazy Pills, which tells an interesting story about David Stuart MacLean’s severe bad reaction to mefloquine – three days delirious in the hospital followed by years of symptoms of anxiety and depression.

Mefloquine was approved by the FDA in 1989 for the prevention of malaria. It was developed by the US military and for a time was the drug of choice for soldiers in malaria-prone areas. It has also been used extensively for civilian travelers.

Initial studies reveals the potential for neuropsychiatric side effects, but suggested that the risk for serious side effects was low, about 1/1000. New evidence presented to the FDA, however, suggests the risk is much higher, leading the FDA to put a black box warning label on the drug. The FDA site on mefloquine (brand name Lariam) states:

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Feb 02 2024

How To Prove Prevention Works

Published by under Logic/Philosophy

Homer: Not a bear in sight. The Bear Patrol must be working like a charm.
Lisa: That’s specious reasoning, Dad.
Homer: Thank you, dear.
Lisa: By your logic I could claim that this rock keeps tigers away.
Homer: Oh, how does it work?
Lisa: It doesn’t work.
Homer: Uh-huh.
Lisa: It’s just a stupid rock.
Homer: Uh-huh.
Lisa: But I don’t see any tigers around, do you?
[Homer thinks of this, then pulls out some money]
Homer: Lisa, I want to buy your rock.
[Lisa refuses at first, then takes the exchange]

 

This memorable exchange from The Simpsons is one of the reasons the fictional character, Lisa Simpson, is a bit of a skeptical icon. From time to time on the show she does a descent job of defending science and reason, even toting a copy of “Jr. Skeptic” magazine (which was fictional at the time then created as a companion to Skeptic magazine).

What the exchange highlights is that it can be difficult to demonstrate (let alone “prove”) that a preventive measure has worked. This is because we cannot know for sure what the alternate history or counterfactual would have been. If I take a measure to prevent contracting COVID and then I don’t get COVID, did the measure work, or was I not going to get COVID anyway? Historically the time this happened on a big scale was Y2K – this was a computer glitch set to go off when the year changed to 2000. Most computer code only encoded the year as two digits, assuming the first two digits were 19, so 1995 was encoded as 95. So when the year changed to 2000, computers around the world would think it was 1900 and chaos would ensue. Between $300 billion and $500 billion were spent world wide to fix this bug by upgrading millions of lines of code to a four digit year stamp.

Did it work? Well, the predicted disasters did not happen, so from that perspective it did. But we can’t know for sure what would have happened if we did not fix the code. This has lead to speculation and even criticism about wasting all that time and money fixing a non-problem. There is good reason to think that the preventive measures worked, however.

At the other end of the spectrum, often doomsday cults, predicting that the world will end in some way on a specific date, have to deal with the day after. One strategy is to say that the faith of the group prevented doomsday (the tiger-rock strategy). They can now celebrate and start recruiting to prevent the next doomsday.

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Nov 16 2023

Trust in Science

Published by under Culture and Society

How much does the public trust in science and scientists? Well, there’s some good news and some bad news. Let’s start with the bad news – a recent Pew survey finds that trust in scientist has been in decline for the last few years. From its recent peak in 2019, those who answered that science has a mostly positive effect on society decreased from 73% to 57%. Those who say it has a mostly negative effect increased from 3 to 8%. Those who trust in scientists a fair amount or a great deal decreased from 86 to 73%. Those who think that scientific investments are worthwhile remain strong at 78%.

The good news is that these numbers are relatively high compared to other institutions and professions. Science and scientists still remain among the most respected professions, behind the military, teachers, and medical doctors, and way above journalists, clergy, business executives, and lawyers. So overall a majority of Americans feel that science and scientists are trustworthy, valuable, and a worthwhile investment.

But we need to pay attention to early warning signs that this respect may be in jeopardy. If we get to the point that a majority of the public do not feel that investment in research is worthwhile, or that the findings of science can be trusted, that is a recipe for disaster. In the modern world, such a society is likely not sustainable, certainly not as a stable democracy and economic leader. It’s worthwhile, therefore, to dig deeper on what might be behind the recent dip in numbers.

It’s worth pointing out some caveats. Surveys are always tricky, and the results depend heavily on how questions are asked. For example, if you ask people if they trust “doctors” in the abstract the number is typically lower than if you ask them if they trust their doctor. People tend to separate their personal experience from what they think is going on generally in society, and are perhaps too willing to dismiss their own evidence as “exceptions”. If they were favoring data over personal anecdote, that would be fine. But they are often favoring rumor, fearmongering, and sensationalism. Surveys like this, therefore, often reflect the public mood, rather than deeply held beliefs.

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Sep 28 2023

Coal vs Natural Gas

Published by under General Science

In the last 18 years, since 2005, the US has decreased our CO2 emissions due to electricity generation by 32%, 819 million metric tons of CO2 per year. Thirty percent of this decline can be attributed to renewable energy generation. But 65% is attributed to essentially replacing coal-fired plants with natural gas (NG) fired plants. The share of coal decreased from 50% to 23% while the share of NG increased from 19% to 38%. Burning coal for energy released about twice as much CO2 as burning NG. Plus, NG power plants are more efficient than coal. The net result is that NG releases about 30% of the CO2 per unit of energy created as does coal.

But – the picture is more complicated than just calculating CO2 release. The implications of a true comparison between these two sources of energy has huge implications for our attempts at reducing climate change. It’s clear that we should phase out all fossil fuels as quickly as possible. But this transition is going to take decades and cost trillions. Meanwhile, we are already skirting close to the line in terms of peak warming and the consequences of that warming. We no longer have the luxury of just developing low carbon technology with the knowledge that it will ultimately replace fossil fuels. The path we take to get to net zero matters. We need to take the path that lowers greenhouse gas (GHG) emissions as quickly as possible. So when we build more wind, solar, nuclear, hydroelectric, and geothermal plants, do we shut down coal, natural gas, or perhaps it doesn’t matter?

If we look just at CO2, it’s a no-brainer – coal is much worse and we should prioritize shutting down coal-fired plants. This may still be the ultimate answer, but there is another factor to consider. NG contains methane, and methane is also a GHG. Per molecule, methane causes 80 times the warming of CO2 over a 20 year period. So any true comparison between coal and NG must also consider methane. (A little methane is also released in coal mining.) But considering methane is extremely complicated, and involves choices when looking at the data that don’t have any clear right or wrong answers.

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Aug 10 2023

The Alzheimer’s Revolution

Decades of complex research and persevering through repeated disappointment appears to be finally paying off for the diagnosis and treatment of Alzheimer’s  disease (AD). In 2021 Aduhelm was the first drug approved by the FDA (granted contingent accelerated approval) that is potentially disease-modifying in AD. This year two additional drugs received FDA approval. All three drugs are monoclonal antibodies that target amyloid protein. They each seem to have overall modest clinical effect, but they are the first drugs to actually slow down progression of AD, which represents important confirmation of the amyloid hypothesis. Until now attempts at slowing down the disease by targeting amyloid have failed.

Three drugs in as many years is no coincidence – this is the result of decades of research into a very complex disease, combined with monoclonal antibody technology coming into its own as a therapeutic option. AD is a form of dementia, a chronic degenerative disease of the brain that causes the slow loss of cognitive function and memory over years. There are over 6 million people in the US alone with AD, and it represents a massive health care burden. More than 10% of the population over 65 have AD.

The probable reason we have rapidly crossed over the threshold to detectable clinical effect is attributed by experts to two main factors – treating people earlier in the disease, and giving a more aggressive treatment (essentially pushing dosing to a higher level). The higher dosing comes with a downside of significant side effects, including brain swelling and bleeding. But that it what it took to show even a modest clinical benefit. But the fact that three drugs, which target different aspects of amyloid protein, show promising or demonstrated clinical benefit helps confirm that the amyloid protein and the plaques they form in the brain are, to some extend driving AD. They are not just a marker for brain cell damage, they are at least partly responsible for that damage. Until now, this was not clear.

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