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Lawrence Hrubes

BBC News - The blind breast cancer detectors - 0 views

  • Gerd Gigerenzer's test In 2006 and 2007 Gigerenzer gave a series of statistics workshops to gynaecologists, and kicked off every session with the same question: A 50-year-old woman, no symptoms, participates in routine mammography screening. She tests positive, is alarmed, and wants to know from you whether she has breast cancer for certain or what the chances are. Apart from the screening results, you know nothing else about this woman. How many women who test positive actually have breast cancer? What is the best answer? nine in 10 eight in 10 one in 10 one in 100 Gigerenzer then supplied the doctors with data about Western women of this age. (His figures were based on US studies from the 1990s, rounded up or down for simplicity - recent stats from Britain's National Health Service are slightly different.) The probability that a woman has breast cancer is 1% ("prevalence") If a woman has breast cancer, the probability that she tests positive is 90% ("sensitivity") If a woman does not have breast cancer, the probability that she nevertheless tests positive is 9% ("false alarm rate") In one session, almost half the gynaecologists said the woman's chance of having cancer was nine in 10. Only 21% said that the figure was one in 10 - which is the correct answer.
markfrankel18

Let's do some math on Ebola before we start quarantining people - Quartz - 0 views

  • The magnitude of false positives for medical tests—a positive test for a condition that a patient does not actually have—is something that is not well understood, even by members of the medical community. We should remember this, as the United States prepares to lock away potential scores of individuals who test positive for Ebola. Many observers do not realize just how many people may spend some time in quarantine when they do not have the dreaded disease.
  • The cognitive psychologist Max Gigerenzer once asked 24 physicians the following hypothetical question, and only two got it right: A test for breast cancer is 90% accurate in identifying patients who actually have breast cancer, and 93% accurate in producing negative results for patients without breast cancer. The incidence of breast cancer in the population is 0.8%. What is the probability that a person who tests positive for breast cancer actually has the disease? Think you know the answer? Many of the physicians in Gigerenzer’s study said there was a 90% probability that a now-terrified patient flagged for breast cancer is an actual victim of the disease. However, the correct probability is less than 10%.
Lawrence Hrubes

My Great-Great-Aunt Discovered Francium. And It Killed Her. - NYTimes.com - 0 views

  • There is a common narrative in science of the tragic genius who suffers for a great reward, and the tale of Curie, who died from exposure to radiation as a result of her pioneering work, is one of the most famous. There is a sense of grandeur in the idea that paying heavily is a means of advancing knowledge. But in truth, you can’t control what it is that you find — whether you’ve sacrificed your health for it, or simply years of your time.
  • How quickly an element decayed and how it did so — meaning which of its component parts it shed — became the focus of researchers in radioactivity. Apart from purely scientific insights, there was a hope that radiation could lead to something marvelous. X-rays, a kind of radiation discovered by Wilhelm Roentgen and produced by accelerated electrons, had already been hailed as a major medical breakthrough and, in addition to showing doctors their patients’ insides, were being investigated as a treatment for skin lesions from tuberculosis and lupus. In her 1904 book “Investigations on Radioactive Substances,” Marie Curie wrote that radium had promise, too — diseased skin exposed to it later regrew in a healthy state. Radium’s curious ability to destroy tissue was being turned against cancer, with doctors sewing capsules of radium into the surgical wounds of cancer patients (including Henrietta Lacks, whose cells are used today in research). This enthusiasm for radioactivity was not confined to the doctor’s office. The element was in face creams, tonics, even candy. According to the Encyclopaedia Britannica article that Curie and her daughter wrote on radium in 1926, preliminary experiments suggested that radium could even improve the quality of soil.
  • Perhaps the most tragic demonstration of this involved workers at the United States Radium Corporation factory in Orange, N.J., which in 1917 began hiring young women to paint watch faces with glow-in-the-dark radium paint. The workers were told that the paint was harmless and were encouraged to lick the paintbrushes to make them pointy enough to inscribe small numbers. In the years that followed, the women began to suffer ghoulish physical deterioration. Their jaws melted and ballooned into masses of tumors larger than fists, and cancers riddled their bodies. They developed anemia and necrosis. The sensational court case started — and won — by the dying Radium Girls, as they were called, is a landmark in the history of occupational health. It was settled in June 1928, four months before Marguerite Perey arrived at the Radium Institute to begin a 30-year career of heavy exposure to radiation.
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  • We know now that alpha and beta particles emitted in radiation attack DNA and that the mutations they cause can lead to cancer. Ingested radioactive elements can concentrate in the bones, where they continue their decay, in effect poisoning someone for as long as that person lives. By the time Perey made her discovery, she was already heavily contaminated. She spent the last 15 years of her life in treatment for a gruesome bone cancer that spread throughout her body, claiming her eyesight, pieces of her hand and most of the years in which she had planned to study francium. As the disease progressed, she warned her students of the horrible consequences of radiation exposure. Francis, my grandfather, says he recalls hearing that when she walked into labs with radiation counters in her later years, they would go off.
  • Over the years, historians have pondered what drove the Curies to throw caution so thoroughly to the wind. Perhaps it was inconceivable to them that the benefits of their research would not outweigh the risks to themselves and their employees. In a field in which groundbreaking discoveries were being made and the competition might arrive there first, speed was put above other concerns, Rona noted. But you almost get the impression that in the Curie lab, dedication to science was demonstrated by a willingness to poison yourself — as if what made a person’s research meaningful were the sacrifices made in the effort to learn something new.
markfrankel18

Correlation is not causation | OUPblog - 0 views

  • A famous slogan in statistics is that correlation does not imply causation. We know that there is a statistical correlation between eating ice cream and drowning incidents, for instance, but ice cream consumption does not cause drowning. Where any two factors –  A and B – are correlated, there are four possibilities: 1. A is a cause of B, 2. B is a cause of A, 3. the correlation is pure coincidence and 4., as in the ice cream case, A and B are connected by a common cause. Increased ice cream consumption and drowning rates both have a common cause in warm summer weather.
  • We know that smoking causes cancer. But we also know that many people who smoke don’t get cancer. Causal claims are not falsified by counterexamples, not even by a whole bunch of them. Contraceptive pills have been shown to cause thrombosis, but only in 1 of 1000 women. Following Popper, we could say that for every case where the cause is followed by the effect there are 999 counterexamples. Instead of falsifying the hypothesis that the pill causes thrombosis, however, we list thrombosis as a known side-effect. Causation is still very much assumed even though it occurs only in rare cases.
  • One could understand a cause, for instance, as a tendency towards its effect. Smoking has a tendency towards cancer, but it doesn’t guarantee it.. Contraception pills have a tendency towards thrombosis but a relatively small one. However, being hit by a train strongly tends towards death. We see that tendencies come in degrees, as do causes, some strongly tending towards their effect and some only weakly.
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  • Correlation does not imply causation. At best it might be taken as indicative or symptomatic of it. And perfect correlation, if this is understood along the lines of Hume’s constant conjunction, does not indicate causation at all but probably something quite different.
markfrankel18

When everything seems like it might cause cancer, here's how scientists determine what ... - 0 views

  • Who decides what constitutes “proof”? Can “proof” come only from experiments? If so, we’re in trouble, because we can never do an experiment in humans for any exposure that is suspected to be harmful.
  • The problem is that as new data come along, what was once proven can become unproven again by new expert panels who now consider this new evidence and come to a different conclusion. This leads to the perhaps uncomfortable definition of “proof” as “a consensus of experts.”
  • The point of emphasis is that there is no hard formula on how to consider the evidence; it is a group decision by a panel of experts (the scientific jury) in which sometimes the epidemiological evidence is so strong that it doesn’t matter whether mice get cancer or not. And sometimes the epidemiology is insufficient to render a verdict on causation and so the toxicology becomes important in making the decision.
Lawrence Hrubes

How Headlines Change the Way We Think - The New Yorker - 0 views

  • As a result of these shifts in perception, problems arise when a headline is ever so slightly misleading. “Air pollution now leading cause of lung cancer,” ran a headline last year in the U.K. paper Daily Express. The article, however, said no such thing, or, rather, not exactly. Instead, it reported that pollution was a leading “environmental” cause; other causes, like smoking, are still the main culprits. It is easy to understand a decision to run that sort of opening. Caveats don’t fit in single columns, and, once people are intrigued enough to read the story, they’ll get to the nuances just the same. But, as it turns out, reading the piece may not be enough to correct the headline’s misdirection. It’s these sorts of misleading maneuvers that Ullrich Ecker, a psychologist and cognitive neuroscientist at the University of Western Australia, was pondering when he decided to test how slight—and slightly misleading—shifts in headlines can affect reading. In Ecker’s prior work, he had looked at explicit misinformation: when information that’s biased influences you, no matter what you’re subsequently told. This time around, he wanted to see how nuance and slight misdirection would work.
Lawrence Hrubes

There's a good reason Americans are horrible at science - Quartz - 0 views

  • There are a number of problems with teaching science as a collection of facts. First, facts change. Before oxygen was discovered, the theoretical existence of phlogiston made sense. For a brief, heady moment in 1989, it looked like cold fusion (paywall) was going to change the world. In the field of medical science, “facts” are even more wobbly. For example, it has been estimated that fewer than 10% of published high profile cancer studies are reproducible (the word “reproducible” here is a euphemism for “not total poppycock”).
  • It’s not possible for everyone—or anyone—to be sufficiently well trained in science to analyze data from multiple fields and come up with sound, independent interpretations. I spent decades in medical research, but I will never understand particle physics, and I’ve forgotten almost everything I ever learned about inorganic chemistry. It is possible, however, to learn enough about the powers and limitations of the scientific method to intelligently determine which claims made by scientists are likely to be true and which deserve skepticism. As a starting point, we could teach our children that the theories and technologies that have been tested the most times, by the largest number of independent observers, over the greatest number of years, are the most likely to be reliable.
Lawrence Hrubes

Cancer Studies Are Fatally Flawed. Meet the Young Billionaire Who's Exposing the Truth ... - 0 views

  • Like a number of up-and-coming researchers in his generation, Nosek was troubled by mounting evidence that science itself—through its systems of publication, funding, and advancement—had become biased toward generating a certain kind of finding: novel, attention grabbing, but ultimately unreliable. The incentives to produce positive results were so great, Nosek and others worried, that some scientists were simply locking their inconvenient data away. Related Stories Nick Stockton Science Gets Better at Being Wrong Katie M. Palmer Science Has Its Problems, But the Web Could Be the Fix Katie M. Palmer Psychology Is in Crisis Over Whether It’s in Crisis The problem even had a name: the file drawer effect.
markfrankel18

Placebo-philes - Anxious Machine - 1 views

  • It's easy to sneer at the placebo effect, or to feel ashamed of it when you're its victim. And that's precisely why I found Felix Salmon's piece revelatory, because instead of sneering at the placebo effect of fancy wine, its marketing, and its slightly higher prices, he thinks we should take advantage of it. If the placebo effect makes us happy, why not take advantage of that happiness?
  • n a recent article for the Atlantic, David H. Freedman argues that there's virtually no scientific evidence that alternative medicine (anything from chiropractic care to acupuncture) has any curative benefit beyond a placebo effect. And so many scientists are outraged that anyone takes alternative medicine seriously. However, there is one area where alternative medicine often trumps traditional medicine: stress reduction. And stress reduction can, of course, make a huge impact on people's health. The Atlantic article quotes Elizabeth Blackburn, a biologist at the University of California at San Francisco and a Nobel laureate. “We tend to forget how powerful an organ the brain is in our biology,” Blackburn told me. “It’s the big controller. We’re seeing that the brain pokes its nose into a lot of the processes involved in these chronic diseases. It’s not that you can wish these diseases away, but it seems we can prevent and slow their onset with stress management.” Numerous studies have found that stress impairs the immune system, and a recent study found that relieving stress even seems to be linked to slowing the progression of cancer in some patients. Perhaps not surprisingly, a trip to the chiropractor or the acupuncturist is much more likely to reduce your stress than a trip to the doctor. If anything, a trip to the doctor makes you more anxious.
markfrankel18

Why We Make Bad Decisions - NYTimes.com - 1 views

  • We need to be aware of our natural born optimism, for that harms good decision making, too. The neuroscientist Tali Sharot conducted a study in which she asked volunteers what they believed the chances were of various unpleasant events’ occurring — events like being robbed or developing Parkinson’s disease. She then told them what the real chances of such an event happening actually were. What she discovered was fascinating. When the volunteers were given information that was better than they hoped or expected — say, for example, that the risk of complications in surgery was only 10 percent when they thought it was 30 percent — they adjusted closer to the new risk percentages presented. But if it was worse, they tended to ignore this new information. This could explain why smokers often persist with smoking despite the overwhelming evidence that it’s bad for them. If their unconscious belief is that they won’t get lung cancer, for every warning from an antismoking campaigner, their brain is giving a lot more weight to that story of the 99-year-old lady who smokes 50 cigarettes a day but is still going strong.
Lawrence Hrubes

The Danger Artist - The New Yorker - 0 views

  • It’s not true that Chris Burden, the profoundly satirical Los Angeles artist who died last week, of cancer, at sixty-nine, had himself shot in the arm for the performance work “Shoot,” in 1971. Rather, he was shot by a friend whose claim to be a marksman proved an overstatement. The .22 bullet was supposed to only graze Burden. The shooter missed. So Burden told me, years ago. He shared with others that he had been frightened of having himself crucified on a Volkswagen, for “Trans-Fixed” (1974), but was pleasantly surprised by how painlessly the thin nails passed through his hands. He went to extremes, but he wasn’t nuts. When, nearly naked and holding his hands behind him, he wriggled across fifty feet of broken glass in “Through the Night Softly” (1973), the glass was the crumbled safety kind—not that that made for comfort. He said that he liked how the scattered bits, glittering on the asphalt of a parking lot, in the black-and-white film of the event, resemble a starry sky.
markfrankel18

Problems with scientific research: How science goes wrong | The Economist - 1 views

  • But success can breed complacency. Modern scientists are doing too much trusting and not enough verifying—to the detriment of the whole of science, and of humanity.
  • A rule of thumb among biotechnology venture-capitalists is that half of published research cannot be replicated. Even that may be optimistic. Last year researchers at one biotech firm, Amgen, found they could reproduce just six of 53 “landmark” studies in cancer research. Earlier, a group at Bayer, a drug company, managed to repeat just a quarter of 67 similarly important papers. A leading computer scientist frets that three-quarters of papers in his subfield are bunk. In 2000-10 roughly 80,000 patients took part in clinical trials based on research that was later retracted because of mistakes or improprieties.
  • Science still commands enormous—if sometimes bemused—respect. But its privileged status is founded on the capacity to be right most of the time and to correct its mistakes when it gets things wrong. And it is not as if the universe is short of genuine mysteries to keep generations of scientists hard at work. The false trails laid down by shoddy research are an unforgivable barrier to understanding.
Lawrence Hrubes

A Pioneer for Death With Dignity - NYTimes.com - 0 views

  • More than two decades before Brittany Maynard’s public advocacy for death with dignity inspired lawmakers in Washington, D.C., and at least 16 states to introduce legislation authorizing the medical practice of aid in dying for the terminally ill, Senator Frank Roberts of Oregon sponsored one of the nation’s first death-with-dignity bills.
  • Medical aid in dying has always had enormous public support. Recent polls by Gallup and Harris show that 69 to 74 percent of people believe terminally ill adults should have access to medical means to bring about a peaceful death. This belief is strong throughout the nation and across all demographic categories, including age, disability, religion and political party.
  • First, the phenomenon of Brittany Maynard has transformed the movement for end-of-life-choice into an unstoppable force. Ms. Maynard was the 29-year-old woman dying of brain cancer, who moved, with her family, from her home in California to establish residency in Oregon and gain access to aid in dying. As her pain and seizures escalated and as inevitable paralysis, blindness and stupor approached, she drank medication obtained under Oregon’s Death With Dignity Act and died quietly in a circle of her loved ones last fall. Her family vows to fulfill her legacy of legal reform in her native California and beyond. Young and old alike identify with Brittany Maynard. Her experience as a refugee for dignity sparks the “aha!” moment when people understand the grave injustice of government’s withholding from a competent, dying adult the elements of choice and control over suffering.
Lawrence Hrubes

Walter Mischel, The Marshallow Test, and Self-Control - The New Yorker - 1 views

  • Mischel’s story isn’t surprising—nicotine is addictive, and quitting is difficult—except for one thing: Mischel is the creator of the marshmallow test, one of the most famous experiments in the history of psychology, which is often cited as evidence of the importance of self-control. In the original test, which was administered at the Bing Nursery School, at Stanford, in the nineteen-sixties, Mischel’s team would present a child with a treat (marshmallows were just one option) and tell her that she could either eat the one treat immediately or wait alone in the room for several minutes until the researcher returned, at which point she could have two treats. The promised treats were always visible and the child knew that all she had to do to stop the agonizing wait was ring a bell to call the experimenter back—although in that case, she wouldn’t get the second treat. The longer a child delayed gratification, Mischel found—that is, the longer she was able to wait—the better she would fare later in life at numerous measures of what we now call executive function. She would perform better academically, earn more money, and be healthier and happier. She would also be more likely to avoid a number of negative outcomes, including jail time, obesity, and drug use.
  • It was not until one day in the late nineteen-sixties, when he saw a man with metastasized lung cancer in the halls of Stanford’s medical school—chest exposed, head shaved, little green “x” marks all over his body, marking the points where radiation would go—that Mischel realized he was fooling himself. Finally, something clicked. From then on, each time he wanted a cigarette (approximately every three minutes, by his count) he would create a picture in his mind of the man in the hallway. As he described it to me, “I changed the objective value of the cigarette. It went from something I craved to something disgusting.” He hasn’t had a smoke since.
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    "Mischel, who is now eighty-four years old, has just published his first popular book, "The Marshmallow Test: Mastering Self-Control." It is part memoir, part scientific analysis, and part self-help guide. In the book, he describes the original impetus for the marshmallow study. At the time, his daughters, Judith, Rebecca, and Linda, were three, four, and five years old, respectively. "I began to see this fascinating phenomenon where they morphed from being highly impulsive, immediate creatures who couldn't delay anything," he told me. "There were these amazingly rapid changes-everything around them was the same, but something inside them had changed. I realized I didn't have a clue what was going on in their heads." He wondered what was it that had enabled them to go from deciding that they wanted to wait to actually being able to do so. He found the answer among their classmates at the Bing preschool."
Lawrence Hrubes

Guns are now killing as many people as cars in the U.S. - The Washington Post - 0 views

  • Medical ailments, such as cancer and heart attacks, kill considerably more people each year than either guns or automobiles, according to the CDC. But firearms and motor vehicles are among the leading non-medical causes of mortality in the United States. They kill more people than falls do each year, and considerably more people than alcohol.
markfrankel18

Shock Me if You Can - NYTimes.com - 1 views

  • Shock long ago went mainstream, raising a question: Can art still shock today? Nudity and raw language are no longer scandalous, and decades of Modernist assaults on formal constraints have dissolved the boundary between art and not-art, high and low. The outcry over “Lady Chatterley’s Lover” and “Tropic of Cancer” seems downright quaint at a moment when millions of suburban mothers are devouring the sadomasochistic fantasy “50 Shades of Grey.”
  • Today shock can seem indistinguishable from scandal, less a side effect of artistic innovation than a ploy ginned up by self-promoting artists and public scolds. But many artists say that generating shock remains the duty of anyone who aims to reflect the real world back at itself. Audiences may be more sophisticated, and jaded, but it is still possible to show them something they may not want to see.
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