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
Spektrum der Wissenschaft
AUS FORSCHUNG WIRD GESUNDHEIT
Wie gut ist die biomedizinische Forschung?
Heute stellen wir die Frage: Wie gut ist die biomedizinische Forschung? Stimmt es, was John Ioannidis von der amerikanischen Universität Stanford behauptet hat, dass die Hälfte aller wissenschaftlichen Artikel falsch sind? Beantworten kann mir diese Frage Professor Ulrich Dirnagl. Er leitet am Berlin Institute of Health das BIH Quest Center, das die Qualität und Ethik in der Wissenschaft erforscht. Er hat John Ioannidis ans BIH eingeladen, um als Einstein BIH Visiting Fellow mit ihm zusammen zu arbeiten.
Dichtung und Wahrheit in der Forschung
Ulrich Dirnagl ist Professor für Neurologie an der Charité – und “Wissenschaftsnarr”, als der er regelmäßig eine Kolumne im “Laborjournal” schreibt. Mit Thomas Prinzler spricht er über Qualität und Ethik in der biomedizinischen Forschung. Denn zu oft würden Ergebnisse weggelassen oder auch gefälscht.
Wo Professor Zufall regiert
Zu wenige Versuchspersonen, unsauber geplante Experimente, keine Replikation der Untersuchung: viele biomedizinische Studien haben Schwächen. So große, dass man stattdessen genauso gut eine Münze werfen könnte, meint der Neurologe Ulrich Dirnagl.
Podcast Spektrum – Wirkstoffradio (André Lampe und Bernd Rupp)
Podcast Kritisches Denken (Philip Barth, Andreas Blessing)
Episode 25 – Qualität in der Forschung
Im ersten Teil des Gesprächs mit Prof. Ulrich Dirnagl von der Charité Berlin sprechen wir über strukturelle Probleme in der Forschungslandschaft, die Reproduzierbarkeitskrise und den p-Wert. Details zur Episode
Podcast Kritisches Denken (Philip Barth, Andreas Blessing)
Episode 26 – Mikrobiomforschung und andere Hype-Zyklen
In Teil 2 des Gesprächs mit Prof. Ulrich Dirnagl unterhalten wir uns über die Mikrobiomforschung und wie Hype-Zyklen in der Wissenschaft verlaufen.
Podcast Gesundheit Macht Politik
Ulrich Dirnagl | Forschung: This is an intergalactic emergency
And here’s a video cast from the European Academy of Neurology
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
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
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
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
- Let’s get this out of the way: Reproducibility is a cornerstone of science: Bacon, Boyle, Popper, Rheinberger
- A ‘lexicon’ of reproducibility: Goodman et al.
- What do we mean by ‘reproducible’? Open Science collaboration, Psychology replication
- Reproducible – non reproducible – A false dichotomy: Sizeless science, almost as bad as ‘significant vs non-significant’
- The emptiness of failed replication? How informative is non-replication?
- Hidden moderators – Contextual sensitivity – Tacit knowledge
- “Standardization fallacy”: Low external validity, poor reproducibility
- The stigma of nonreplication (‘incompetence’)- The stigma of the replicator (‘boring science’).
- How likely is strict replication?
- Non-reproducibility must occur at the scientific frontier: Low base rate (prior probability), low hanging fruit already picked: Many false positives – non-reproducibility
- Confirmation – weeding out the false positives of exploration
- Reward the replicators and the replicated – fund replications. Do not stigmatize non-replication, or the replicators.
- Resolving the tension: The Siamese Twins of discovery & replication
- Conclusion: No scientific progress without nonreproducibility: Essential non-reproducibility vs . detrimental non-reproducibility
- Further reading