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Bad Science. Hw 4. Re-Stating the Correlation. Researchers find a correlation between eating bacon and low sperm count. “Researchers found a correlation between eating bacon and low sperm count. Therefore, processed meat causes lower sperm count.”. More Causes.
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Re-Stating the Correlation Researchers find a correlation between eating bacon and low sperm count. “Researchers found a correlation between eating bacon and low sperm count. Therefore, processed meat causes lower sperm count.”
More Causes “Bacon causes a low sperm count because it makes you fat, and that messes with the hormones that regulate sperm development. ‘Alternatively’ processed meat (including bacon) makes you fat, and this leads to low sperm count.”
Parts as Causes “Eating a bacon sandwich causes low sperm count, because bacon is on a bacon sandwich and bacon causes low sperm count.”
Eggs and Arteries According to the article “Egg Yolks almost as bad as smoking,” Dr. David Spence found that “people who eat egg yolks regularly have about 2/3 as much plaque buildup as smokers.”
Eggs and Bacon Eggs are often served with unhealthy meals– omelets with bacon and cheese, cheeseburgers, fried rice, greasy Korean soup… Maybe it’s the things we eat with eggs that cause the plaque build up.
X causes A causes B http://www.youtube.com/watch?v=68f2VqQY6z0 “Abusive parents caused me to eat bacon, and bacon causes lower sperm count. So my abusive parents caused my low sperm count.”
Hypothetical Imaginethat science shows that some treatment that is important to you is no better than a placebo, and only works because people believe it does—it’s only the placebo effect. Imagine that the science is really good and not flawed or biased or poorly conducted.
Defenses of Placebos When presented with this question, people produce a wide range of defenses of placebos– reasons why we should still undergo certain treatments, even if all the scientific evidence said they work only through the placebo effect.
Common Defenses Sometimes they accept that treatments were placebos, but argued that that was OK: • Sometimes there are no other treatments. • If it works, it doesn’t matter how. • There are no side-effects, so taking a placebo can be better than taking “real” medicine. • The placebo effect is a mental effect. But sometimes the problem is mental too.
Traditional Chinese Medicine In the case of Traditional Chinese Medicine, I have heard that if science-based medical trials (experiments) had results that said TCM was only a placebo, there are other, non-science-based reasons for believing that TCM is real medicine, and really works (not only through the placebo effect).
“Western” vs. “Science-based” I often hear TCM contrasted with “Western” medicine. I don’t like to talk that way, I think it confuses the issues.
Hong Kong Museum of Science Qi Meridians The Endocrine System
From Wikipedia “In 1110, a Chinese medical text specified the use of gypsum… as well as saponin from the beans of Gleditschiasinensis to extract hormones from urine, a process of using natural soaps which was not discovered elsewhere until the use of digitonin by Adolf Windaus (1876–1959) in 1909.In modern medicine, the extraction of these hormones from urine is a standard practice, yet centuries before this the Chinese had used it to treat hypogonadism, impotence, spermatorrhea, dysmenorrhea, leukorrhea, and even stimulating the growth of beards (since they knew that castration resulted in the loss of ability to grow a beard).”
Participation “Dear Michael, I know of one Chinese medical researcher who does science based medicine. He/ she recently did an experiment that showed…”
“Western” vs. “Science-based” There is lots of non-science-based Western medicine. Homeopathy, electroconvulsive therapy, chiropractic, faith healing, naturopathy, quack therapies for cancer…
Acupuncture as SBM Additionally, there is no reason to think that some TCM might become science-based medicine in time. For example, some studies have suggested promising effects for acupuncture for some ailments. There are also suggestions about plausible scientific mechanisms that would explain how acupuncture worked. If all that turns out– then acupuncture will be science-based.
Project 523 and Malaria For example there’s lots of evidence that the Chinese herb, qinghao青蒿素(artemisia) is useful in curing malaria. (Mao’s army tested 5,000 TCM remedies for malaria, and this was the only one that worked. But it worked!)
Science-based Medicine The difference between science-based medicine (SBM) and non-SBM is that 1. SBM has evidential support in the form of statistically significant RCTs – or– 2. SBM has scientifically plausible mechanisms that explain how it works.
Defenses of TCM Common defenses of TCM I’ve encountered are: • It has a long history of many thousand years. • It’s holistic and flexible, treating the person, not the symptoms. • It’s herbal or natural rather than chemical. • There are Chinese explanations for why it works.
Defenses of TCM More defenses: 5. TCM has spiritual effects beyond the physical ones. 6. TCM gets taught in schools, and published in journals– even in the West! (It is recognized by authorities.) 7. It’s culturally important to use it.
1. Sometimes There are No Other Treatments There’s no cure for the common cold. The common cold is a virus that mutates very rapidly. Because it is a virus, antibiotic medications can’t kill it, and because it mutates so rapidly, vaccines can’t prevent it.
Zinc Lozenges Some things actually do make you feel better– chicken soup, surprisingly, has some medical evidence backing it up. I eat it when I’m sick. But I also buy zinc lozenges. I know they’re no better than placebo lozenges– but that doesn’t mean they aren’t better than nothing. Placebo lozenges do cause improvement!
2. If it works, it doesn’t matter how A common defense of “placebo medicine” (medicine that was no better than a placebo) is that it didn’t matter whether the treatment caused the improvement or our beliefs about the treatment caused the improvement— The improvement is all that matters!
Nocebos MSG is not harmful, but people who think it harms them often suffer. Wind farms are not harmful, but people who live near them often suffer.
The Point Something is wrong with the argument “if it works, it doesn’t matter how it works” for placebos. The same argument could be given for nocebos: “if it hurts, it doesn’t matter how it hurts: so stop using MSG, and get rid of those wind farms!”
3. There are No Side Effects “The placebo effect is real medicine, because it triggers the body’s healing system. One could argue that this is the best medicine, in fact, since: a. drugs do not trigger the healing system and b. the placebo effect has no side effects.” Deepak Chopra
Bullshit! As to Chopra’s first claim, it’s bullshit. Placebo’s don’t “trigger the healing system”– they don’t do anything. That’s part of the definition of ‘placebo’. All real treatment has the same positive effect as placebos and a lot more. The real stuff.
Can Placebos Have Side Effects? As we’ve just seen, there are side effects even to sugar pills: nocebo effects. But let’s suppose we’re considering a case where people believe that treatment X will help them, and X performs no better than a sugar pill in double-blind randomized placebo-controlled trials. Can X still have side effects?
Yes! Remember that a lot of evidence suggests SSRI’s (selective serotonin reuptake inhibitors, a kind of antidepressant drug) work no better at curing depression than placebos. This does not mean they do other things no better than placebos. They are very good at making you unable to eat, sleep, or have sex.
Harmful “Natural” Ingredients Pure sugar pills (or saltwater injections) can’t harm you any more than your beliefs can (which can be significantly). But invasive treatments or treatments with pharmacologically active ingredients can harm you, even if they are only as good as a placebo at helping you.
Cancer in Taiwan Taiwan has the highest per-capita incidence of UUC (upper urinary tract cancer) of anywhere in the world. Plants of the genera Ephedra and Asarum produce the toxic chemical aristolochicacid which causes UUC. TCM herbal remedies contain lots of these plants, and tests have shown they contain aristolochic acid as well.
Kidney Failure in Belgium In a case report in “Nature” in 2011, a “slimming clinic” in Belgium where women were taking Chinese herbal remedies led to more than 100 women suffering kidney failure and many of them later developing cancer… From aristolochicacid, the same thing making Taiwan #1 in UUC!
Other Harmful Side-Effects Here’s a bottle of Saiga Antelope Horn Powder. The Saiga Antelope is critically endangered, so the fact that people take these pills is currently harming endangered species.
Opportunity Costs Sometimes “side-effects” are worth it. For example, if the disease will kill you unless you suffer through a painful debilitating treatment, it may be worth it to undergo the treatment– at least that way you’ll be alive!
Chemotherapy Lots of cancer is treatable, and if detected early enough, almost (but never quite) 100% curable. For example, some kinds of lymphoma can be cured in otherwise healthy patients with chemotherapy and radiation therapy. These treatments are not pleasant, and cause a lot of suffering. But the alternative is death: herbal teas don’t help.
4. Sometimes the Disease is Mental One common defense of placebos is that sometimes, the symptoms were entirely mental: pain, unhappiness, stress, nervousness, irritability– or things that these psychological states can cause: ulcers, high heart-rate, pimples, low sex drive, etc.
Expectations If the symptoms are mental, then one might suspect that a “purely mental” cure would work. The placebo effect works by manipulating your expectations. So maybe the placebo is the best cure for certain illnesses.
Nocebo and Placebo To some extent, this is true: people are sick because they believe they should be (nocebo effect) and they are cured by undergoing a treatment that they believe should work (placebo effect).
Chronic Fatigue Syndrome But just because a condition is “psychological” does not mean that it can be cured by the placebo effect. For example, Chronic Fatigue Syndrome (CFS) is thought by many to be an illness with purely psychological causes. People try lots of treatments for CFS, but none of them work. This is proof that not all psycholgical illnesses can be cured with a placebo.
Medicalizing Problems Additionally, giving people pills or shots or magic incantations or whatever for psychological illnesses can “medicalize” those illnesses. For example, if you give women a pill for sexual problems, then even if it works only as a placebo, they may conclude that their problems were chemical in nature, rather than psychological, a problem with relationships.
Traditional Chinese Medicine I don’t pretend to know a lot about TCM. I know very little. I don’t want to argue here against TCM. This class is “Logic and Critical Thinking” not “Traditional Chinese Medicine.”
Hypothetical But it’s the hypothetical that’s important to me: imagine that science-based medicine concludes that some treatment in TCM is no better than a placebo… Should we stop using that treatment? If TCM is better than a placebo, we don’t have to answer this question. But what if it isn’t…?
Not a Doctor I’m not a (medical) doctor, and my job isn’t to teach you medicine, and I can’t teach you medicine. My goal is to make you think about medicine (and other things) critically. What are rational ways to respond to arguments– for example, arguments that certain treatments are no better than a placebo?
1. Long History “Traditional Chinese Medicine works– how can it not? It’s been around for 2,000 years. The basic ideas are set forth in ‘The Yellow Emperor’s Inner Cannon’, published around 100 BCE. If it didn’t work wouldn’t someone have noticed in the past 2000 years?”
Astrology Sometimes things don’t work, and they survive. For example, almost every Western newspaper contains a horoscope, a prediction of how your day (week) will go, based on your Zodiac sign. I’m told this happens in Chinese newspapers too.