Category: Reproducibility

Diet: Is nutrition science a more reliable source of advice than your grandmother?

Meat consumption is bad for your health. It gives you cancer, heart attacks, stroke, you name it. Says nutrition science. And they must know. After all, it’s a science. Is it, really?

A few years ago, Jonathan Schoenfeld and John Ioannidis took a standard cookbook and randomly selected 50 frequently occurring ingredients (sugar, coffee, salt, etc.). They then carried out a systematic literature search, asking whether there were epidemiologicial studies that had investigated the cancer risk of these ingredients. And they found what they were looking for. For 80% of the ingredients at least one study existed, for many even several. Of 264 of these studies, 103 found that the ingredient investigated increased the risk of cancer, while 88 reduced the risk! So  after all Joe Jackson was right: ‘Everything gives you cancer’! But wait a minute: Milk? Veal? Orange juice? Continue reading

Why do WE trust the Intergovernmental Panel on Climate Change, but not the climate skeptics?

The societal acceptance of the results of our daily work as scientists is dire. The majority of the US population does not explain evolution with Darwin, but with Holy Scripture. Measles is on the rise again worldwide, because vaccination opponents smell a conspiracy by the pharmaceutical industry to make children autistic. A substantial proportion of the population does not believe that climate change is man-made. They believe that if you fear climate change you are hysterical, and manipulated  by interested scientists competing for funding and fame. Homeopaths treat disease with sugar pills, while the health insurers, with our money, foot the bill.

A popular recipe against this increasing rejection of relevant scientific findings is to provide more and better science education in schools and the media. Inspired by a lecture of the American sociologist and historian of science Steven Shapin, I respectfully disagree.

Continue reading

Microbe Mania with Melancholic Microbes

Recently in a train station book shop I stood gaping in astonishment in front of a thematically highly specialized book display. It was the bowels-brain table. The books piled up on it promised enlightenment about how the bowel and in particular its contents influence us – yes – how, they verily steer our emotions. A selection of book titles: “Shit-Wise – How a Healthy Intestinal Flora Keeps us fit”; “Bowels heal brain heal body”; “Happiness begins in the bowels”, or “The second brain – How the bowels influence our mood, our decisions and our feeling of wellbeing”. Newspapers, magazines and the internet can also tell us this. The wrong bowel bacteria make us depressive – but the right ones make us happy … which is why yogurt helps against depression. Continue reading

Could gambling save science?

U.S. economist Robin Hanson posed this question in the title of an article published in 1995. In it he suggested replacing the classic review process with a market-based alternative. Instead of peer review, bets could decide which projects will be supported or which scientific questions prioritized. In these so-called “prediction” markets, individuals stake “bets” on a particular result or outcome. The more people trade on the marketplace, the more precise will be the prediction of outcome, based as it is on the aggregate information of the participants. The prediction market thus serves the intellectual swarms. We know that from sport bets and election prognoses. But in science? Sounds totally crazy, but it isn’t. Just now it is making its entry into various branches of science. How does it function, and what does it have going for it? Continue reading

Your Lab is Closer to the Bedside Than You Think

 

With a half-page article written about him and his study, an Israeli radiologist unknown until then made it into the New York Times (NYT 2009). Dr. Yehonatan Turner presented computer-tomographic scans (CTs) to radiologists and asked them to make a diagnosis. The catch: Along with the CT a current portrait photograph of the patient was presented to the physicians. Remember, radiologists very often do not see their patients, they make their diagnosis in a dark room staring at a screen. Dr. Turner in his study used a smart cross-over design: He first showed the CT together with a portrait photograph of the patient to one group of radiologists. Three months later the same group had to make a diagnosis using the same CT, but without the photo. Another group of radiologists were first given only the CT and then, three months later the CT with photo. A further control group examined only the CTs, as in routine practice. The hypothesis: When a radiologist is exposed to the individual patient, and not only to an anatomical finding on a scan, she will be more conscious of her own responsibility, hence findings will be more thorough and diagnosis more accurate. And in fact, this is what he found. The radiologists reported that they had more empathy with the patient, and that they “felt like doctors”. And they spotted more irregularities and pathological findings when they had the CT and photo in front of them than when they were only looking at the CT (Turner and Hadas-Halpern 2008).

So how about showing researchers in basic and preclinical biomedicine photos of patients with the disease they are currently investigating in a model of the disease? Continue reading

Predators in the (paper) forest

 It struck at the end of July.  A ‘scandal’ in science shook the Republic.  Research  by the NDR  (Norddeutscher Rundfunk), NDR (Westdeutscher Rundfunk) and the Süddeutsche Zeitung revealed that German scientists are involved in a “worldwide scandal”.  More that 5000 scientists in German universities, institutes and federal authorities had, with public funds, published their work in on-line pseudoscientific publishing houses that do not comply with the basic rules and for assuring scientific quality.  The public and not just a few scientists heard for the first time about “predatory publishing houses” and “predatory journals”.

Predatory publishing houses, whose presentation in phishing mails is quite professional, offer scientists Open Access (OA) publication of their scientific studies at a cost, whereby they imply that their papers will be peer reviewed.   No peer review is carried out, and the articles are published on the web site of these “publishing houses”, which however are not listed in the usual search engines such as PubMed.  Every scientist in Germany finds several such invitations per day in his or her e-mails.  If you are a scientist and receive none, you should be worried about it. Continue reading

No scientific progress without non-reproducibility?

Slides of my talk at the FENS Satellite-Event ‘How reproducible are your data?’ at Freie Universität, 6. July 2018, Berlin

 

  1. Let’s get this out of the way: Reproducibility is a cornerstone of science: Bacon, Boyle, Popper, Rheinberger
  2. A ‘lexicon’ of reproducibility: Goodman et al.
  3. What do we mean by ‘reproducible’? Open Science collaboration, Psychology replication
  4. Reproducible – non reproducible – A false dichotomy: Sizeless science, almost as bad as ‘significant vs non-significant’
  5. The emptiness of failed replication? How informative is non-replication?
  6. Hidden moderators – Contextual sensitivity – Tacit knowledge
  7. “Standardization fallacy”: Low external validity, poor reproducibility
  8. The stigma of nonreplication (‘incompetence’)- The stigma of the replicator (‘boring science’).
  9. How likely is strict replication?
  10. Non-reproducibility must occur at the scientific frontier: Low base rate (prior probability), low hanging fruit already picked: Many false positives – non-reproducibility
  11. Confirmation – weeding out the false positives of exploration
  12. Reward the replicators and the replicated – fund replications. Do not stigmatize non-replication, or the replicators.
  13. Resolving the tension: The Siamese Twins of discovery & replication
  14. Conclusion: No scientific progress without nonreproducibility: Essential non-reproducibility vs . detrimental non-reproducibility
  15. Further reading

Open Science Collaboration, Psychology Replication, Science. 2015 ;349(6251):aac4716

Goodman et al. Sci Transl Med. 2016;8:341ps12.

https://dirnagl.com/2018/05/16/can-non-replication-be-a-sin/

https://dirnagl.com/2017/04/13/how-original-are-your-scientific-hypotheses-really