Anyone who follows this blog must get the impression that I am a nag and misanthropist. Nothing and nobody seems to please me. I alway find the sample sizes too small, the statistics too lazy, the data hand-picked, or the results too positive and the conclusions drawn from them too exaggerated. Also, I find the peer review system unreliable, not to mention support of mainstream research and giving to those who already have (‘Matthew effec’) by the funding agencies. I even dared to critsize the Nobel Prize an atavistic instrument celebrating the lonely, white male reseacher and genius. Artificial intelligence I find stupid, and the academic career system the core of all these evils. To name but just a few examples.
But that is far from the truth! I am a science enthusiast! I am convinced that science is the best that the 1500 grams of protein and fat encapsulated in our skull have ever produced. Yes, I am a science nut. So with this entry, at the beginning of the new decade, let’s start with a proper hymn to biomedical science. 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
You got to see this youtube video! Hectically cut sequences of busy young scientists in high-tech laboratories wearing lab coats, nerdy looking guys are soldering electronic circuits and stare into oscilloscopes, we are taken on a roller coaster ride through an animated brain chockful of tangled nerve cells. And in between all this, on stage at the California Academy of Sciences, car and rocket manufacturer Elon Musk announces his latest vision in a messianic pose: The symbiosis of the human brain with artificial intelligence (AI)! This time his plan to save mankind does not involve mass evacuation to Mars, but will be realized by a revolutionary Brain Machine Interface (BMI), designed and manufactured by his company Neuralink. You may have guessed it, this has caused a tremendous media hype all over the world. The verdict in the press and on the net was: “Musk at his best, a bit over the edge, but if HE announces a breakthrough like that there must be something to it”. The more cautious asked: “But couldn’t this be dangerous for mankind? Do we need a new ethic for stuff like this?” Continue reading
Damn! What an effort: Generation of a knockout mouse line, back crossing in background strain and litermates, all the genotyping. Followed by a plethora of experiments in a disease model: surgery, magnetic resonance imaging, histology, behavioral studies, and so on. Finally the result: No phenotype! The knockout mouse appears to be a mouse like any other. Not different from the wild type background strain. But wait, we rather need to phrase it like this: We did not find a statistically significant difference between knockout and wild type. So we cannot even conclude that wild type are like knowout mice, but rather: If there is a difference, it might be smaller than the detectable effect size, depended on sample size, error level (alpha and beta) and the variance of our results. But we had planned our experiments well: The sample size was determined a priori, and chosen so that we would have been able to detect a difference on the order of one standard deviation. This is what statisticians call a Cohen’s d of 1, which is considered a substantial effect. We could not have done more animals than the (34!), because of limited ressources, the duration of the PhD thesis, and the timing of the grant. But what now? Write a paper? Reporting a NULL result? How would this look like in a resume, besides, who cares about NULL results, and which reputable journal would publish them at all? Continue reading
A study in this weeks Nature (Vrselja et al. ) has created an immediate media frenzy. Nature puts it like this: ‘Pig brains kept alive outside body for hours after death’ and ‘Revival of disembodied organs raises slew of ethical and legal questions about the nature of death and consciousness.’ The New York Times: ‘In a study that raises profound questions about the line between life and death, researchers have restored some cellular activity to brains removed from slaughtered pigs.; STAT: ‘The pigs were dead. But four hours later, scientists restored cellular functions in their brains’ etc.
That sounds spectacular. But if one reads the study (and the commentaries) is easy to spot that there are two main deficiencies: 1) The study lacks novelty, and 2) The assertion that it presents a relevant step towards restoring brain function after a prolonged interruption of cerebral blood flow is not only exaggerated, but simply wrong. Continue reading
‘Unfortunately, we have to inform you that after thorough review [YOUR FAVORITE FUNDING ORGANISATION] must reject your application’. Most of us know this sentence all to well, as most rejection letters of our grant applications contain it in a similar form. From a purely statistical point of view, we receive such letters quite frequently. In German biomedicine, the funding rates are between 5 and 25 %, depending on funder and program. Upon receiving a rejection we often feel personally offended. After all, we have put down our best ideas, often had already included some preliminary results and proposed experiments we had already conducted, even beautified the document with a lot of prose, and flattered the most important potential reviewers with strategically placed quotations, etc. And then the rejection! So we had to start over from the beginning, rewrite everything, submit it again, perhaps to another funding agency. This is how we spend a substantial fraction of our days at the office, if we don’t review applications of our colleagues. On average, scientists spend 40% of their time writing or reviewing applications. Continue reading