https://www.yahoo.com/news/beware-those-scientific-studies-most-wrong-researcher-warns-164336076.html
Washington (AFP) - A few years ago, two researchers took the 50 most-used ingredients in a cook book and studied how many had been linked with a cancer risk or benefit, based on a variety of studies published in scientific journals.
The result? Forty out of 50, including salt, flour, parsley and sugar. "Is everything we eat associated with cancer?" the researchers wondered in a 2013 article based on their findings.
Their investigation touched on a known but persistent problem in the research world: too few studies have large enough samples to support generalized conclusions.
But pressure on researchers, competition between journals and the media's insatiable appetite for new studies announcing revolutionary breakthroughs has meant such articles continue to be published.
"The majority of papers that get published, even in serious journals, are pretty sloppy," said John Ioannidis, professor of medicine at Stanford University, who specializes in the study of scientific studies.
This sworn enemy of bad research published a widely cited article in 2005 entitled: "Why Most Published Research Findings Are False."
Since then, he says, only limited progress has been made.
Some journals now insist that authors pre-register their research protocol and supply their raw data, which makes it harder for researchers to manipulate findings in order to reach a certain conclusion. It also allows other to verify or replicate their studies.
Because when studies are replicated, they rarely come up with the same results. Only a third of the 100 studies published in three top psychology journals could be successfully replicated in a large 2015 test.
Medicine, epidemiology, population science and nutritional studies fare no better, Ioannidis said, when attempts are made to replicate them.
"Across biomedical science and beyond, scientists do not get trained sufficiently on statistics and on methodology," Ioannidis said.
Too many studies are based solely on a few individuals, making it difficult to draw wider conclusions because the samplings have so little hope of being representative.
- Coffee and Red Wine -
"Diet is one of the most horrible areas of biomedical investigation," professor Ioannidis added -- and not just due to conflicts of interest with various food industries.
"Measuring diet is extremely difficult," he stressed. How can we precisely quantify what people eat?
In this field, researchers often go in wild search of correlations within huge databases, without so much as a starting hypothesis.
Even when the methodology is good, with the gold standard being a study where participants are chosen at random, the execution can fall short.
A famous 2013 study on the benefits of the Mediterranean diet against heart disease had to be retracted in June by the most prestigious of medical journals, the New England Journal of Medicine, because not all participants were randomly recruited; the results have been revised downwards.
So what should we take away from the flood of studies published every day?
Ioannidis recommends asking the following questions: is this something that has been seen just once, or in multiple studies? Is it a small or a large study? Is this a randomized experiment? Who funded it? Are the researchers transparent?
These precautions are fundamental in medicine, where bad studies have contributed to the adoption of treatments that are at best ineffective, and at worst harmful.
In their book "Ending Medical Reversal," Vinayak Prasad and Adam Cifu offer terrifying examples of practices adopted on the basis of studies that went on to be invalidated, such as opening a brain artery with stents to reduce the risk of a new stroke.
It was only after 10 years that a robust, randomized study showed that the practice actually increased the risk of stroke.
The solution lies in the collective tightening of standards by all players in the research world, not just journals but also universities, public funding agencies. But these institutions all operate in competitive environments.
"The incentives for everyone in the system are pointed in the wrong direction," Ivan Oransky, co-founder of Retraction Watch, which covers the withdrawal of scientific articles, tells AFP. "We try to encourage a culture, an atmosphere where you are rewarded for being transparent."
The problem also comes from the media, which according to Oransky needs to better explain the uncertainties inherent in scientific research, and resist sensationalism.
"We're talking mostly about the endless terrible studies on coffee, chocolate and red wine," he said.
"Why are we still writing about those? We have to stop with that."
Checking out at the supermarket, the young cashier suggested to the much older woman that reusable grocery bags were a good idea as plastic bags weren’t good for the environment.
The woman apologized and explained, “We didn’t have this ‘green thing back in my earlier days.” The young cashier responded, “That’s our problem today – your generation did not care enough to save our environment for future generations.” She was right our generation didn’t have the ‘green thing’ in its day. Back then, we returned milk bottles, lemonade bottles and beer bottles to the shop. The shop sent them back to the plant to be washed and sterilized and refilled, so it could use the same bottles over and over. So, they really were recycled. But we didn’t have the “green thing” back in our day. Grocery shops bagged our groceries in brown paper bags, that we re-used for numerous things, most memorable besides household bags for rubbish, was the use of brown paper bags as book covers for our schoolbooks. This was to ensure that public property (the books provided for our use by the school), was not defaced by our scribbling. Then we were able to personalize our books on the brown paper bags. But too bad we didn’t do the “green thing” back then. We walked up stairs, because we didn’t have a lift in every supermarket, shop and office building. We walked to the local shop and didn’t climb into a 300-horsepower machine every time we had to go half a mile. But she was right. We didn’t have the “green thing” in our day Back then, we washed the baby’s Terry Towelling nappies because we didn’t have the throwaway kind. We dried clothes on a line, not in an energy-gobbling machine burning up 3 kilowatts ……. wind and solar power really did dry our clothes back in our early days. Kids had hand-me-down clothes from their brothers or sisters, not always brand-new clothing.
But that young lady is right; we didn’t have the “green thing” back in our day. Back then, we had one radio or TV in the house – not a TV in every room and the TV had a small screen the size of a big handkerchief (remember them?), not a screen the size of Scotland In the kitchen. We blended and stirred by hand because we didn’t have electric machines to do everything for us. When we packaged a fragile item to send in the mail, we used wadded up old newspapers to cushion it, not Styrofoam or plastic bubble wrap. Back then, we didn’t fire up an engine and burn petrol just to cut the lawn. We pushed the mower that ran on human power. We exercised by working so we didn’t need to go to a health club to run on treadmills that operate on electricity. But she’s right; we didn’t have the “green thing” back then. We drank from a tap or fountain when we were thirsty instead of using a cup or a plastic bottle every time we had a drink of water. We refilled writing pens with ink instead of buying a new pen, and we replaced the razor blades in a razor instead of throwing away the whole razor just because the blade got dull. But we didn’t have the “green thing” back then. Back then, people took the bus and kids rode their bikes to school or walked instead of turning their Mums into a 24-hour taxi service in the family’s $70,000 People Carrier which cost the same as a whole house did before the “green thing.” We had one electrical outlet in a room, not an entire bank of sockets to power a dozen appliances and we didn’t need a computerized gadget to receive a signal beamed from satellites 23,000 miles out in space in order to find the nearest pub! But isn’t it sad that the current generation laments how wasteful we old folks were just because we didn’t have the “green thing” back then?
We don’t like being old in the first place, so it doesn’t take much to piss us off…especially when the “advice” is being offered by a tattooed, multiple pierced smartarse who can’t work out the change without the cash register telling them how much it is!
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