#143 - John Ioannidis, M.D., D.Sc.: Why most biomedical research is flawed, and how to improve it
Episode Stats
Length
1 hour and 52 minutes
Words per Minute
159.32411
Summary
John Ioannidis is a physician, scientist, writer, and a Stanford University professor. He has extensive training in mathematics, medicine, and epidemiology, and is one of the smartest people I've ever met. In this episode, we talk about his journey from Greece to the United States, his seminal work, and how he uses mathematical models to make sense of complex problems.
Transcript
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Hey, everyone. Welcome to the drive podcast. I'm your host, Peter Atiyah. This podcast,
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head over to peteratiyahmd.com forward slash subscribe. Now, without further delay,
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here's today's episode. I guess this week is John Ioannidis. John is by all estimates,
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a polymath. He's a physician, scientist, a writer, and a Stanford University professor.
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He has extensive training in mathematics, medicine, epidemiology. He's just generally one of the
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smartest people I've ever met. And I've had the luxury of knowing John for probably about nine
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years. And anytime I get to interact with him, whether it's over a meal or more formally through
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various research collaborations, it's just always an incredible pleasure.
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John studies scientific research itself, a process known as meta-research, primarily in clinical
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medicine, but also somewhat in the social sciences. He's one of the world's foremost experts on the
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credibility of medical research. He's the co-director of the Meta-research Innovation Center
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at Stanford. In this episode, we talk about a lot of things. We talk about his journey from Greece
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to the United States, but we talk a lot about some of his seminal papers. You're going to see me
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reference a number of papers, beginning with, I think, one of the most famous papers he's written,
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although by citation, it turns out to not be the most famous. There's actually papers that even
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exceed it, which is an amazing paper where he describes through a mathematical model why most
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published research in the biomedical field is incorrect, which is obviously out of the gate,
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a staggering statement. We go on to discuss a number of his other seminal papers,
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and then really kind of tackle some of the hard issues in medical research, including
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my favorite topic, nutritional epidemiology. As always, John is candid and full of insight,
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so I'm just going to leave it at that and hope that you trust me and make time to listen to this
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one. So please, without further delay, enjoy my discussion with John Ioannidis.
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John, this is really exciting for me to be as close to sitting down with you as I can be during this
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time. I've been wanting to interview you for as long as I've had a podcast, and obviously,
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we've known each other for probably close to 10 years now. Of course, you first came on my radar
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in 2005 with a paper that we're going to spend a lot of time discussing today. But
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before we get to that, how would you describe yourself to people? Because you have such a
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unique background. I think that it's very difficult to know yourself, and I've been struggling
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on that front for a long time. So I'm trying to be a scientist. I think that this is not an easy job.
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It means that you need to reinvent yourself all the time. You need to search for new frontiers,
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for new questions, for new ways to correct errors and to correct your previous self
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in some way. So under that denominator of scientists in the works, probably it would be a good place to
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put my whereabouts. Now, your background is also in mathematics. And I think that's part of my
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appreciation for you is the rigor with which you bring mathematics to the study of science. And in
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particular, we're going to discuss some of your work and how you use mathematical models as tools
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to create frameworks around this. Now, you were born in the US, but grew up in Greece. Is that correct?
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Indeed. I was born in New York, in New York City, but I grew up in Athens. And I always loved mathematics.
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I think that mathematics are the foundation of so many things. And they can really transform our
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approach to questions that without mathematics, it would be very difficult to make much progress.
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How did you navigate your studies? Because you were obviously very prolific in mathematics. If I
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recall reading somewhere in one of your bios, you even won the highest honor that a graduating college
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student could win in mathematics in Greece at the time. How did you decide to also pursue something in
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the biological sciences in parallel as opposed to staying purely in the natural or philosophical
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sciences of mathematics? Medicine had the attraction of being a profession where you can save lives.
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And I think that intellectual curiosity is very interesting, but the ability to make a difference
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for human beings and to save lives, to improve their quality of life, seemed to be, at least in my eyes
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as a young person, something that was worthwhile pursuing. I had a very hard time to choose what
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pieces of mathematics and science and medicine I could combine in what I wanted to do. I think that I
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have tried my hands in very different things. I have probably failed in all of them. But in some ways,
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I saw that these were complementary. So I believe that medicine is amazing in terms of its possibilities
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to help people. You need, however, very rigorous science. You need very rigorous scientific method
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to be applied if you want to get reliable evidence. Then you also need quantitative approaches. You need
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quantitative tools to be able to do that. So I think that none of them is possible to dispense without
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really losing the hole and losing the opportunity to do something that really matters eventually.
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And your parents were physicians as well. Is that correct?
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Indeed. Both of them were physicians, actually physician scientists. So I did have an early
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exposure to an environment where I could hear their stories of clinical exposure. At the same time,
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I could see them working on their research. I remember these big tables with scientific papers spread
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all over them and with what were the early versions of computerized research. I think that I had the
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chance to be exposed to software and computers in an early phase because my father and my parents were
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interested in doing research. So you finished medical school and your postgraduate training also in
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Greece, or did you do part of that in the United States? I finished medical school in Greece in Athens,
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in the National University of Athens. And then I went to Harvard for residency training. And then Tufts
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General Medical Center for training in infectious diseases. At the same time, I was also doing joint
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training in healthcare research. So it was very interesting and fascinating years learning from
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And who were some of the people that you think back as having kind of shaped your thinking during those
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In the medical school, I had some great teachers. One of them was the professor of epidemiology,
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Dmitry Trikopoulos, who was also chair of epidemiology at Harvard. And he had some really great
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statisticians in his team. So from the first year at medical school, I went to meet them and tried to use
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every textbook that they could give me and every resource that I could play with. In my residency
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training, I was very fortunate to meet a great physician scientist, especially in infectious
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diseases, actually. Bob Mellering was the physician in chief and professor at Harvard, professor of
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medical research as well. And he was really an amazing personality in terms of his clinical acumen and
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his approach to patients. Also, his very temperate mode of dealing with very serious problems and
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dissecting through the evidence in trying to make decisions and, of course, start with making
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diagnosis. At the end of my residency training, I had the pleasure to meet the late Tom Chalmers,
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along with Joe Lau. They were at Tufts at that time. And my meeting with them was really a revelation
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because they were the ones who were advancing the frontiers of evidence-based medicine. Evidence-based
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medicine had just been coined as a term, pretty much, by the McMaster team, David Sackett and Gordon
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Wyatt. And Tom Chalmers was the first person in the U.S. to design a randomized trial. He was also one of
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the first to perform meta-analysis that had a major impact in medical science. At the time that I met them,
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they had just published an influential paper on cumulative meta-analysis in the New England Journal of
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Medicine. And it was a revelation for me because somehow what they were proposing was mixing
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mathematics, rigorous methods, evidence, and medicine in one coherent whole, which seemed to be
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a forlorn hope until then for me. I was just seeing lots of clinical exposures that there was very little
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evidence to guide us. There was no data or very poor data and a lot of expert-based opinion guiding
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everything that was being done. And so this is just temporarily, I mean, Chalmers died in the
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mid-90s. So this is what, the early 90s that you were fortunate enough to meet him? Yes. I met him in
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1992 and he died about five years later. I was grateful that I had the opportunity to work with him
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and also with Joseph Lau, who was at that time at Tufts Union Medical Center, which I went eventually to
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do my fellowship training. Because there are so many things I want to talk about, John, and we don't
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have the luxury of spending 12 hours together. I'm going to fast forward about a decade. I'm going to
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fast forward to 2005, to that paper that I alluded to at the outset, which was the first time your work
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came onto my radar, which is not to say anything other than that's just the first time I became aware
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of sort of the gravity of your thinking. Can you talk a little bit about that? It was in PLOS One,
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was that paper, correct? Yes. It was in PLOS Medicine.
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PLOS Medicine. Okay. So this is basically an open source journal that I think another Stanford
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professor actually was one of the guys behind this journal, if I recall. Pat Brown was one of the
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forces behind PLOS, correct? Well, it was a transformative move at that time,
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trying to create a new standard for medical journals. I think that now this has become
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very widespread in a way. But I think back then it was something new, something that was a new
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frontier in a sense. So you wrote a paper that on the surface seems, I mean, highly provocative,
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right? The title of the paper is something to the effect of why most published clinical research
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is untrue. I mean, that's the gist of it. Can you walk people through the methodology of this?
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It's a theoretical paper, but explain to people who maybe don't have the understanding of mathematics
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that you do, how you were able to come to such a stark conclusion, which I want to point out one
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thing. I'll give you why I had an easy time believing the results of your paper is my mentor had shared
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with me a statistic when I was, you know, sort of doing my postdoctoral training, which I found hard
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to believe. But when I realized it was true, became the bookend to your claim. And that was some at the
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time, something to the tune of 70% of published papers were never cited again, outside of auto
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citation, meaning outside of the author citing his or her own work. And if you think about that for a
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moment, if 70% of work can't even be cited by one additional person down the line, that tells you
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it's, you know, either irrelevant or wrong. So again, that's not the same thing that you said,
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but it at least primed me to kind of listen to the message you were talking about. So talk a little
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bit about that paper. That paper, as you say, it's a mathematical model that is trying to match
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empirical data that had accumulated over time, both in my work and also in the work of many other
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scientists who were interested to understand the validity of different pieces of research that was
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being produced. I think that many of us had been disillusioned that when evidence-based medicine
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started, we thought that now we have some tool to be able to get very reliable evidence for decision
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making. And very quickly, we realized that biases and results that could not be replicated and
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results that were overturned and results that were unreliable were the vast majority. It was not
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something uncommon. It was the rule that we had either unreliable evidence or actually, perhaps even
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more commonly, no evidence. So it's an effort, that paper, to put a mathematical construct together
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that would try to explain what is going on and would also try to predict in some ways what might
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happen if some of the circumstances would change in terms of how we do research. So the model makes
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for a framework that is trying to calculate what is the chance that if you come up with a Eureka,
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a statistically significant result, that you claim I have found something, I have found some effect that is
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not null. There is some treatment effect here, there is some not zero that I'm talking about. What are the
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chances that this is indeed a non-null effect, that we're not seeing just a red herring? And in order to
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calculate the chances that this is not just a red herring, you need to take into account what is your prior
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chances that you might be finding something in the field that you're working. There are some fields that
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probably have a higher chance of making discoveries compared to others. If you're unlucky to work in a
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field that there's nothing to be discovered, you may be wasting your time and publishing one million
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papers, but there's nothing to be discovered. So it's going to be one million papers that end up with
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nothing. Conversely, there may be other fields that may be more rich in discovery, both the field and
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the tools, the methods, the designs of the studies that we throw at trying to answer these questions
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can be informative. The second component is in what environment of power are we operating? Meaning,
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is the study large enough to be able to detect non-null effects of some size of interest? Or
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maybe there are true effects out there, but our studies are very small, and therefore they're not
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able to detect these effects. And in my experience until that time, I had seen again and again lots of
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very small studies floating around with results that were very questionable, that could not be matched
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with other efforts, especially when we were doing larger studies, most of them seemed to go away.
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And power is important, not only because if you don't have enough power, you cannot detect things
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that exist. What is equally bad or probably worse is that if you operate in an environment of low power,
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when you do get something detected, it is likely to be false. And here comes the other factor that is
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compounding the situation, bias, which means that you have some results that for whatever reason,
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bias makes them to seem statistically significant, while they should not be. And bias could take
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zillions of forms. I think that throughout my career, I feel like I'm struggling with bias, with my own
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biases, and with biases that I see in the literature. But bias means that you could have conscious,
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unconscious, or subconscious reasons why a result that should have been null somehow is transformed
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into a significant signal. It could be publication bias, it could be selective reporting bias, it could be
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multiple types of confounding bias, it could be information bias, it could be many, many other things that turn
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null results into seemingly significant results while they are not. Then you have to take into account the
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universe of the scientific workforce. We're not talking about a single scientist running all the studies.
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It's not just a single scientist or a single team. We have currently about 35 million people who have
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co-authored at least one scientific paper. We have many, many scientists who might be trying to attack
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the same scientific question. And each one of them is contributing to that evidence. However,
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there's an interplay of all these biases with all of these scientists. So if you take into account that
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multi-scientist environment, multi-effort environment, you need to account for that in your calculations.
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Because if you, for example, say, what are the chances that at least one of these scientists will find some
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significant signal, this is a very different situation compared to just having one person
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taking a shot and just taking a single shot. So this is pretty much what the model tried to take
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into account, putting these factors together, and then trying to see what you get under realistic
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circumstances for these factors. These factors would vary from one field to another. They would be
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different, for example, if we're talking about exploratory research with observational data versus
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small randomized trials versus very large phase three or even mega trials. It would be different if we're
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talking about massive testing, like what we do in genetics versus highly focused testing of just one
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highly specified pre-registered hypothesis that is being attacked. Running the calculations, the model
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shows that in most circumstances where both biomedical research, but I would say most other fields of
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research are operating, if you get a nominally statistically significant signal with a traditional
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p-value of slightly less than 0.05, then the chances that you have a red herring, that this is not true,
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that it is a false positive, are higher than 50%. There's a huge gradient, and in some cases it may be
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much lower. The false positive rate may be much, much lower, and in others it would be much higher.
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But in most circumstances, the chances that you got it wrong are pretty high. They're very high.
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That's actually a very elegant description of that paper. I want to go back and unpack a few things
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for people who maybe don't have some of the acumen down. So let's go a bit deeper into what a p-value
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is. Everybody hears about it, and everybody hears the term statistically significant. So maybe explain
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what a p-value is, explain statistical significance, and explain why it's not necessarily the same as
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clinical significance and why we shouldn't confuse them. I think that there's major misconceptions
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around significance. What we care in medicine is clinical significance, meaning if I do something,
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or if I don't do something, would that make a difference to my patient? Or it could be in public
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health, to the community, to cohorts of people, to healthy people who want to have preventive measures,
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and so forth. Do I make a difference? Does it matter? Is it big enough that is worthwhile the cost,
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the potential harms, the implementation effort, perhaps other alternatives that I have? How does
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that compare to these alternatives? Maybe they're better, or cheaper, or easier to implement, or have
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fewer harms? So this is really what we want to answer, but unfortunately most of the time we are stuck with
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trying to answer a very plain frequentist approach question, which boils down to statistical significance.
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Typically this boils down to a p-value threshold of 0.05 for most scientific fields. Over the years
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there's many scientific fields that have diversified, and they have asked for more stringent levels of
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statistical significance. A couple of years ago, along with many other people, we suggested that fields that
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have not diversified and they do not adjust their levels of statistical significance to more stringency.
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By default, they should be using a more stringent threshold. For example, use a threshold of 0.005 instead
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of 0.05. However, most scientists are trained with statistics light to use some statistical test that
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gives you some statistic that eventually translates to a p-value. And what that p-value means, it needs to
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be interpreted as what are the chances that if I had an infinite number of studies like this one, I would
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get a result that would be as extreme or more extreme. And even that is not a complete definition because
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it does not take into account bias. Because maybe you would get a result that is as extreme, but it's
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largely because of bias. For example, there's many, many fields that you can easily get p-values that are
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astronomical. They're not just less than 0.005, but they may be 10 to the minus 100 with some of the large
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databases that we have. We can easily get to astronomically small p-values. But this doesn't
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mean much. It could just mean that you have bias and this is why you get all these astronomically low
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p-values, but they don't really mean that the chance of getting such an extreme result is extremely
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implausible and that there's something there. It just means that certainly there's bias. No more than that.
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There has been what I call the statistics wars over the last several decades. People have tried to
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diminish the emphasis on statistical significance. I think I have been in the camp of those who have
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argued that we should diminish emphasis or at least try to improve the understanding of what that means
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for people who use and interpret these p-values. In the last few years, this has become probably more
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aggressive. Many great methodologists have suggested that we should completely abandon statistical
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significance, that we should just ban the term, never use it again, and just focus on effect sizes,
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focus on how much uncertainty we have about effect sizes, focus on perhaps Bayesian interpretation of
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research. I have been a little bit reluctant about adopting the ban statistical significance approach
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because I'm afraid that we have all these millions of scientists who are probably not very properly
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trained to understand statistical significance, but they're completely not trained at all to understand
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anything else that would replace it. So, in some ways, for some types of designs also, I would argue
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that if you pre-specify and if you are very careful in registering your hypotheses and you have a protocol
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that you deposit, for example, what is happening or should be happening with randomized trials, and you have
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worked through this, that it makes sense that your hypothesis is clinically important, that the effect
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size that you're trying to pick is clinically meaningful, it is clinically significant, then I would argue
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that statistical significance and using a p-value threshold, whatever that is, depending on how you
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design the study, makes perfect sense. It's actually a very transparent way of having some rules of the game
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that then you try to see whether you manage to succeed or not. So, if you remove
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these rules of the game after the fact in these situations, it may make things worse because you
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will have a situation where people will just get some results and then they will be completely open
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to interpret them as they wish. And we see that they interpret them as they wish even now without
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any rules in the game, or at least by removing those rules post-hog. But if we could have some rules
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for some types of research, I think that this is useful. For other types of research, I'm willing to
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promote better ways of interpreting results, but this is not going to happen overnight. We have to take
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for granted that most scientists are not really well trained in statistics, and they will misuse and
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misinterpret and misapply statistics, unfortunately. So, we need to find ways that we will minimize the harm,
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the harm. We will minimize the error and maximize in medicine, the clinically significant pieces,
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and in other sciences, the true components of the research enterprise.
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Now, at the other side of that statistical field is power, right? So, we go from alpha to beta.
00:26:18.040
And you alluded to it earlier. I want to come back to it because you actually said something very
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interesting. I think most people who dabble enough in the literature understand that if you underpower
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a study, so if you have too few samples, too few subjects, whatever the case might be,
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and you fail to reach statistical significance, it's not clear that you failed to reach statistical
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significance because you should be rejecting the null hypothesis or because you didn't have a large
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enough sample size. So, that's always the fear, right? The fear is that you get a false negative.
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But you said something else that I thought was very interesting, if I heard you correctly, which was,
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no, you actually run the risk of a false positive as well if you're underpowered. Can you say more
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about that? Indeed. In an underpowered environment, you run the risk of having higher rates of false
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positives if you take the performance of the field at large. You know, if you take hundreds and thousands
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of studies that are done in an underpowered environment. Even if you manage to detect the
00:27:28.680
real signals, you know, signals that do exist, if these signals are detected in an underpowered
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environment, their estimates will be exaggerated compared to what the true magnitude is. And in many
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situations, both in medicine and in other sciences, it's not important so much to find whether there's
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some signal at all, which is what an null hypothesis is trying to work around. But how big is the signal? I mean,
00:27:56.680
if a treatment has a minuscule benefit, then I wouldn't care about it. I wouldn't use it because the cost and
00:28:03.560
the harms and everything on the other side of the balance is not making it worth it. So, most scientific fields,
00:28:12.600
have been operating in underpowered environments. And there's many reasons for that. And it varies
00:28:18.040
a little bit from one field to another, but there's some common denominators. Number one, we have a very
00:28:23.720
large number of scientists. Scientists are competitive. There's very limited resources for science. It means
00:28:29.640
that each one of us can get a very thin slice of resources. We need to prove that we can get significant
00:28:35.880
results so as to continue to be funded and to be able to advance in our career. This means that
00:28:43.240
we are stuck in a situation where we need to promote seemingly statistically significant results,
00:28:48.920
even if they're not. We need to do very small studies with these limited resources and then do
00:28:54.440
even more small studies rather than aim to do a more definitive large study. There's even a disincentive
00:29:01.160
incentive towards refuting results that are not correct because that means that you feel that
00:29:07.080
you're back to square zero. You cannot make a claim for continuing your funding. All the incentives,
00:29:11.960
at least until recently, have been aligned towards performing small studies in very selectively
00:29:19.160
reported circumstances and with flexibility in the way that results are analyzed and presented. And
00:29:25.320
I think that this leads to very high rates of results that are either completely false positives or they
00:29:33.240
may be pointing to some real signal, but the estimate of the magnitude of the signal is grossly exaggerated.
00:29:41.320
In recent years, we have started seeing the opposite phenomenon as well. We start seeing some fields that
00:29:48.840
have overpowered studies. Instead of just having very small studies, in some fields we have big data.
00:29:55.560
which means that you can access records, medical records from electronic health records on millions of
00:30:01.880
people, or you may have genetic information that is highly granular and gives you tons of information.
00:30:10.760
And big data are creating an opposite problem. It means that you're overpowered and you can get
00:30:18.120
statistically significant results that have no clinical meaning, that have no meaning really.
00:30:23.960
And even with a tiny little bit of bias, you may get all these signals just because bias is there.
00:30:31.160
So you're just measuring bias. You're just getting a big scale assessment of the distribution of bias in
00:30:38.840
your data sets. That's becoming more of a problem in some specific fields. I think that the growth of this
00:30:46.520
type of problem will be faster compared to the growth of the problem of small underpowered studies.
00:30:52.840
I think in most fields, it's a more common problem though, until now, that we have very small studies
00:30:58.840
rather than very large studies. Now, you've commented on GWAS studies. Do you want to talk a little bit
00:31:05.400
about that here? It sort of fits into this a little bit, doesn't it?
00:31:08.040
Genetics was something that I was very interested in from my early years of doing research because
00:31:15.560
it was a new frontier for quantitative approaches. Lots of very interesting methodology was being
00:31:20.920
developed in genetics. Many of the questions of evidence that had been stagnating in other
00:31:26.600
biomedical fields, they had a new opportunity to give us some new insights with much larger scale
00:31:32.680
evidence in genetics compared to what we had in the past when we were trying to measure things one at
00:31:38.760
a time, especially genetics was a fire hose of evidence in some way. So I found it very exciting.
00:31:46.120
And for many years, I did a lot of genetic research. I still do some. And very early on, we realized
00:31:53.640
through genetics that the approach that we had been following in most traditional epidemiology,
00:32:00.120
like looking at one risk factor at a time and trying to see whether it is associated with some
00:32:05.000
disease outcome was not getting very far. We could see in genetic epidemiology of candida genes
00:32:13.320
that most of these papers that were looking at one or a few genes at a time with association with
00:32:18.280
some outcome, just trying to cross the threshold of statistical significance and then claiming success,
00:32:23.720
they were just false positives. We saw that pretty early. It took some time for people to be convinced,
00:32:29.240
but then they were convinced and genetics took some steps to remedy this. They decided to do very
00:32:35.640
large studies to start with. They also decided to look at the entire genome, look at all the factors
00:32:41.800
rather than one at a time. And they also decided to join forces, not have each scientist try to publish
00:32:48.680
their results alone, but share everything, have a common protocol, put all the data together to maximize
00:32:55.880
power, to maximize standardization, to maximize transparency also, and then report the cumulative
00:33:04.120
results from the combined data from all the teams that had contributed to these large meta-analysis of
00:33:10.920
primary data. So this is a recipe that I think should be followed by many other fields, especially fields
00:33:18.840
that work with observational data in epidemiology. And some fields have started moving in that direction
00:33:24.280
as well, but not necessarily as much as the revolution that happened in genetics and population genomics.
00:33:31.320
So I was going to actually ask you exactly that question. I was going to save it for a bit later,
00:33:35.400
but let's do it now. Why did the field of genetics basically have the ability to self-police
00:33:41.480
and undergo this cultural shift in a way that, let's just put every card on the table here,
00:33:46.360
nutritional epidemiology has not. I mean, nutritional epidemiology, which we're going to spend a lot of
00:33:51.240
time talking about, is the antithesis of that. And it continues to propagate subpar information,
00:33:58.120
which is probably the kindest thing I could say about it. So what is it culturally about these two
00:34:03.880
fields that has produced such stark contrasts in the response to a crisis?
00:34:10.280
There's multiple factors. One reason is that genetics managed to have better tools for measurement
00:34:17.640
compared to nutritional epidemiology. We managed to decode the human genome. So we developed platforms
00:34:24.360
that could measure the entire variability more or less in the human genome with pretty high accuracy.
00:34:31.480
If you have genotypic platforms that have less than 0.01% error rate, this means that you have very
00:34:37.480
accurate measurement. As opposed to nutrition where the traditional tools have been questionnaires or
00:34:44.120
survey tools that have very high biases, very high recall bias, very low accuracy, and they do not
00:34:52.600
really capture the diversity of nutritional factors with equal granularity as we can capture the genetics
00:35:01.000
in their totality of the human genome. The second reason was that I believe in genetics there were no
00:35:07.400
strong priors, no strong beliefs, no strong opinions, no strong experts who would fight with their lives for
00:35:15.880
one gene variant versus another. We had some, you know, I think that some of us probably might have
00:35:21.320
published about one gene and then we would fiercely defend it because obviously if you publish a paper,
00:35:28.680
you don't want to be proven wrong, I think it's very human. But it was nothing compared to the scale that you see
00:35:35.320
in nutrition research where you have a very strong expert opinion base, people who have created careers and
00:35:43.880
they feel very strongly that this type of diet is saving lives and it should have policy implications,
00:35:50.680
it should change the world, it should change our guidelines, it should change everything.
00:35:55.240
Many of these beliefs are interspersed with religious or cultural or, you know, non-scientific beliefs
00:36:03.640
in shaping what we think is good diet. And as you realize, none of that really exists for genetics,
00:36:10.200
you know, polymorphism RS 2492-14 is unlikely to be endorsed by any religious, cultural, political,
00:36:20.600
or dietary proponents. It's a very different beast and I think that you can be more neutral
00:36:27.400
with genetics research because of this objectivity as opposed to nutrition where there's a lot of
00:36:34.120
heavy beliefs interspersed. Methodologically also genetics advanced faster. Nutrition has been stuck mostly
00:36:42.760
in the era of using p-values of 0.05 thresholds and using those thresholds in mostly post hoc research,
00:36:51.240
research that is not registered, that is selectively presented. People are trained in a way that they
00:36:58.920
need to play with the data, they need to torture the data, they need to try to unearth interesting
00:37:05.080
associations. And in some cases, of course, this becomes extreme like what we have seen in the
00:37:11.000
Cornell case where, you know, pretty much goes into the situation where you have fraud. I mean,
00:37:17.400
it's not just poorly done research, it's fraudulent research. But fraudulent research aside, even
00:37:24.120
research that is not fraudulent in nutrition has some standards of methods that are pretty suboptimal
00:37:29.640
compared to what genetics has adopted, that they decided that we have such a huge multiplicity that
00:37:36.200
we need to account for that. So, you know, we're not going to claim success for a p-value of 0.05.
00:37:41.480
We will claim success for a p-value of 10 to the minus 8. And if it's not that low, then forget it.
00:37:47.640
That's not really a finding. We need to get more data before we can say whether we have a finding or not.
00:37:53.960
Or they decided that they will share data, that they will create large coalitions of researchers
00:37:59.000
who would all share their data. They would standardize their data. They will standardize
00:38:02.440
the analysis. They would perform analysis in a very specific way. And they would also sometimes,
00:38:09.880
actually, I think this is becoming the norm, have two or three analyst teams analyze the same data
00:38:15.480
and make sure that they get the same results. These principles and these practices have started
00:38:21.400
being used in fields like nutrition, but to a much lesser extent. And I think that gradually we will
00:38:27.000
see more of that, but it's going to take some time. So there's multiple scientific and behavioral and
00:38:35.640
cultural and statistical and methodological reasons why these fields have not progressed
00:38:41.720
at the same pace of revolutionizing their research practices.
00:38:46.120
Let's talk a little bit about Austin Bradford Hill. I'm guessing you didn't have a chance to meet him.
00:38:51.400
He died in 91. Would you have crossed paths with him at all?
00:38:54.520
No, I didn't have that fortune, unfortunately. Do you think he would be rolling around in his
00:39:01.080
grave right now if he saw what was being employed based on the criteria he set forth, which I also
00:39:08.200
want to talk about your thoughts around the revision of these. But even if you just take his 10 criteria,
00:39:13.000
which we'll go through for a moment as a bit of a background on epidemiology, do you think that
00:39:17.720
what he had in mind is what we're doing today? I think that Austin Bradford Hill was very thoughtful.
00:39:25.480
He was one of the fathers of epidemiology. And of course, he didn't have the measurement tools and
00:39:32.200
the capacity to run research in such large scale as we do today. But he was spot on in coming up with
00:39:40.040
good questions and asking the right questions, asking the important questions. So his criteria,
00:39:46.280
I don't think that he thought of them as criteria. And I don't think that he ever believed that they
00:39:52.600
should be applied as a hard rule to arbitrate that we have found something that is causal versus
00:40:00.040
something that is not causal. If you read through the paper, it's a classic. It's very obvious that he
00:40:06.840
has a very temperate approach. He has a very cautious approach. Basically, he says none of these items
00:40:13.400
is really bulletproof. I can always come up with an example where it doesn't work.
00:40:19.480
And I think that this is really telling what a great scientist he was, because indeed in science,
00:40:25.080
there's hardly anything that is bulletproof. I don't know. The laws of gravity might be bulletproof,
00:40:30.840
but even those, as you realize, they're just only down to atomic levels. Yeah, exactly. You know,
00:40:36.360
in the theory of relativity, they would start failing. So he was very cautious. I think that
00:40:42.360
paper had tremendous impact. I think that we have not been very cautious in moving forward with many
00:40:49.000
of our observational associations and the claims that we have made about them. I don't want to give
00:40:54.920
a nihilistic perspective. And I don't want to give, let's say, a very negative perspective of
00:41:00.600
epidemiology because we run the risk of entering the other side where you will have some science
00:41:05.880
deniers saying, so you're not certain. And therefore we can have more air pollution. You know, we can
00:41:12.520
have more pesticides. We can have more. That's not clearly the case. I mean, we have very solid evidence
00:41:19.480
for many observational associations. There's not the slightest doubt that tobacco is killing right
00:41:26.040
and left. It's likely to kill 1 billion people over the last century. Let's go through tobacco as
00:41:32.600
the poster child for Bradford Hill's criteria. So I'm going to rattle off the quote unquote criteria
00:41:40.120
and just use tobacco as a way to explain it. So let's start with strength. How does the association
00:41:47.480
between tobacco and lung cancer fit in terms of causality vis-a-vis this criteria of strength?
00:41:55.000
It is huge. I mean, we do not see odds ratios of 10, 20, and 30, as we see with tobacco, with many
00:42:02.840
types of cancer and with other outcomes like cardiovascular disease. And I think that that
00:42:09.880
really stands out. And we see that again and again and again. We see very strong signal. We see signals
00:42:16.520
that are highly replicable. And that's the exception. In most of what we do nowadays in epidemiology,
00:42:24.680
we don't see odds ratios of 20. If I see an odds ratio of 20 in my calculations, I'm almost certain
00:42:31.240
that I have something wrong. I always go back and check and I find an error that I have done.
00:42:35.880
Yeah, you're probably off by a log if you're getting a 20 nowadays.
00:42:41.880
Probably two log. I think in genetics, we are dealing actually with odds ratios of 1.01 at the time.
00:42:51.880
So 1.01 may still be real. And of course, you know, then the question is...
00:42:58.660
It's unlikely to be clinically relevant, but how much certainty can you get even for its presence?
00:43:04.180
Yeah. So the strength is huge. You really essentially covered the next one, which is
00:43:07.700
consistency. If you look at all of the studies in the 1950s and the 1960s, they were all really
00:43:13.060
moving in the same direction. And that's whether you looked at physicians who were smokers,
00:43:17.220
non-physicians who were smokers, whichever series of data you looked at, you basically saw this 10x
00:43:23.940
multiplier in smoking. And I think on average, it worked out to be about 14x. There was about a 14
00:43:31.620
times higher chance. I mean, that's a staggering number. What about specificity? What does specificity
00:43:38.900
refer to here? I think that if you have such strength and such consistency, I would probably not
00:43:47.540
worry that much about the rest of the criteria. You know, I think that criteria like specificity or
00:43:55.940
like analogy, they're far more soft in terms of what they would convey. And also, we just don't know
00:44:05.620
the nature of nature in how it operates. Many phenomena may be very specific, but it doesn't
00:44:12.900
have to be so. We should not take it for granted that we should see perfect specificity or low
00:44:18.580
specificity. We see many situations where you have multi-dimensional situations of causality.
00:44:25.460
You have multiple factors affecting some outcome, or you have one factor affecting multiple outcomes.
00:44:32.500
The density of the webs of causality can be highly unpredictable. So I would not worry that much
00:44:39.700
about other criteria if you have some strength and consistency being so impressive in these cases.
00:44:50.100
Now, in most cases, we don't have that, right? We'll get an odds ratio of 1.14, which of course is a 14%
00:44:58.100
relative increase as opposed to 14x. So in those situations, when strength and consistency are out
00:45:05.300
the window, which is essentially true of everything in nutritional epidemiology, I can't really think
00:45:10.820
of examples in nutritional epi where you have strength and consistency.
00:45:15.060
Well, major deficiencies, I think, would belong to the category of very clear signals.
00:45:20.740
Major nutritional deficiencies, you know, if you have like...
00:45:25.620
Sure, sure, yeah. Or, you know, thiamine deficiency where you're out to lunch, yeah.
00:45:30.100
Yeah. But do you then look at... I mean, even biological gradient gets very difficult
00:45:36.020
with the tools of nutritional epi. Do you start to look at experiment? Plausibilities,
00:45:41.060
to me, has always struck me as a very dangerous one because, I don't know, it just seems a bit of
00:45:50.260
I think the first question is whether you can get experimental evidence. To me, that's the priority.
00:45:57.940
And I realize that in some circumstances, when you know that you're dealing with
00:46:02.260
highly likely harmful factors, you cannot really have equipoise to do randomized trials. But for
00:46:10.020
most situations in nutrition, to take nutrition as the example that we have been discussing,
00:46:15.140
you can do randomized trials. And actually, we have done randomized trials. It's not that we're not
00:46:19.140
doing randomized trials. We have done many thousands of randomized trials. Most of them,
00:46:23.780
unfortunately, are pretty small and underpowered. And they suffer from all the problems that we
00:46:29.140
discussed earlier with underpowered studies that are selectively reported, with no pre-registration,
00:46:34.740
and with kind of haphazardly done analysis and reporting. I mean, they're not necessarily better
00:46:40.660
than observational data that suffer from the same problems. But we also have a substantial number of
00:46:47.700
very large randomized trials in nutrition. We have over 200 large randomized trials. Most of those
00:46:54.820
focus on specific nutrients or supplementations. Some are looking at diets like Mediterranean diet.
00:47:03.460
And with very few exceptions, they do not really show the benefits that were suspected or were proposed
00:47:10.020
in the observational data. There are exceptions, but there are not that many. That, to me, suggests that
00:47:16.660
most likely the interpretation that most of the observational signals are false positives or
00:47:21.620
or substantially exaggerated is likely to be true. We shouldn't be throwing out the baby with the
00:47:26.980
bathwater. There may be some that are worth pursuing and that may be true. And I think that this means
00:47:31.780
that we need to do more trials. The counter argument would be that, well, in a randomized trial,
00:47:37.380
especially a large one, especially with long-term follow-up, people will not adhere to what you
00:47:41.620
tell them to do with their diet or nutrient intake or supplementation. My response to this is that
00:47:49.220
when it comes to getting evidence about what people should eat, that lack of adherence is part of the
00:47:56.740
game. It's part of real life. So if a specific diet is in theory better than another, but people cannot
00:48:04.580
adhere to that. It's not really better because people cannot use it. So I get the answer to the
00:48:09.460
question that I'm interested in, which is, is that something that will make a difference?
00:48:14.900
Of course, it does not prove that biochemically or in a perfect system or in the perfect human
00:48:21.540
who is eating like a robot, that would not be helpful. But I don't care about treating robots. I
00:48:28.340
care about managing and helping real people. I agree with that completely, John. I would throw
00:48:33.940
in one wrench to that, which is in a world of so much ambiguity and misinformation, I do think it's
00:48:41.380
important to separate efficacy from effectiveness. What you're of course saying is in the real world,
00:48:46.660
only effectiveness matters. So real world scenarios with real world people. But I still think there is
00:48:52.740
a time and a place for efficacy. We do have to know what is the optimal treatment under perfect
00:48:58.980
circumstances if we want to have any chance at, for example, informing policy. I'll give you an example.
00:49:06.740
Food stamps. Should food stamps preferentially target the use of certain foods over others? Well,
00:49:14.020
again, if you had really efficacious data saying this type of food is worse than that type of food,
00:49:20.820
you could steer people towards healthier foods. It could impact the way we subsidize certain foods.
00:49:26.740
In other words, it's really all about changing the food environment. So it's, it is very hard to follow.
00:49:32.420
I think any diet is that is not the standard American diet. So anytime you opt out of the
00:49:37.860
standard American diet, whether it be into a Mediterranean diet or a vegetarian diet or a
00:49:42.740
low carbohydrate diet, or basically anything that's not the crap that we're surrounded by requires an
00:49:48.900
enormous effort. And I think a big part of that is because there is still so much ambiguity around
00:49:56.340
what the optimal nutritional strategies are. We haven't answered the efficacy question because I
00:50:01.220
think we keep trying to answer the effectiveness question. I agree. And I think I would not abandon
00:50:06.980
efforts to get some insights on efficacy, but we're not really getting these insights the way that we have
00:50:13.540
been doing things. I think that if you want to get answers on efficacy, there are options. One is
00:50:20.260
through the experimental approach. So you can still run randomized trials, but you can do them under
00:50:25.940
very controlled supervised circumstances that, you know, people are in a physiology or metabolism
00:50:33.060
clinic that they're being followed very stringently on what they eat and what happens to them. And you can
00:50:37.780
measure very carefully these biochemical and physiological responses. I think that a second
00:50:43.220
approach in the observational world or between the observational and the randomized is Mendelian
00:50:49.060
randomization studies with the advent of genetics. We have lots of genetic instruments that may be used to
00:50:56.660
create designs that are fairly equivalent to a randomized design. So you can get some estimates that are not
00:51:04.500
perfect because Mendelian randomization has its own assumptions and sometimes these are violated, but at
00:51:10.180
least I think that they go a step forward in terms of the credibility of the signals that you get. And
00:51:18.420
then you have the pure observational evidence, which I don't want us to discard it completely. I think that
00:51:24.180
these are data we should need to use them. We just need to interpret them very cautiously. If we use some of the
00:51:29.700
machinery that we have learned to deploy in other fields, for example,
00:51:35.380
one approach is what I call the environment-wide or exposure-wide association testing. Instead of
00:51:40.260
testing and reporting on one nutrient at a time, you just run an analysis of
00:51:44.900
all the nutrients that you have collected information on
00:51:47.860
and you can also do it for all the outcomes that you have collected information on. So that would be an exposure
00:51:53.620
outcome-wide association study. And then you report the results, taking into account the multiplicity
00:52:00.020
and also the correlation structure between all these different exposures and outcomes.
00:52:04.420
You get a far more transparent and complete picture. And if you get signals that seem to be recurrent and
00:52:11.860
replicable across multiple data sets, multiple cohorts that you run these analysis, you start having
00:52:19.860
higher chances of these signals to be reflecting some reality. Still, it's not going to be perfect
00:52:27.300
because of all the problems that we mentioned, but it is better compared to what we do now where we just
00:52:32.500
go after finding yet one more association, one at a time, and coming up with yet another paper that is
00:52:39.060
likely to be very low credibility. John, if your 2005 paper on the frequency with which we were going to come
00:52:47.460
across valid scientific publications is arguably the one that's... Is that your most cited paper?
00:52:54.980
No, it's not the most highly cited. It's received, I think, close to 10,000 citations, but for example,
00:53:01.300
the Prisma statement for meta-analysis has received far more.
00:53:05.220
Okay. Well, I was going to assume that the 2005 paper was the most cited, but I was going to say the
00:53:11.620
most entertaining is your 2012 paper, which is the systematic cookbook review. And again, this is
00:53:21.300
just one of those things where I remember the moment this paper came out and just the absolute belly
00:53:27.540
laughing that I had reading this. And frankly, the sadness I had reading this because it is a sarcastic
00:53:34.820
commentary in a way on a problem that I think plagues this entire field. So in this paper,
00:53:42.580
you basically, I don't know if it was randomly, but you selected basically 50 common ingredients
00:53:50.180
from a cookbook, right? Was there any method behind how you did this or was it purely random?
00:53:55.620
Well, we used the Boston cookbook that has been published since the 19th century. And we randomly
00:54:05.780
chose ingredients by selecting pages and then within those, the recipes and the ingredients that
00:54:12.100
were in these recipes. So yes, it is 50 ingredients, a random choice thereof, and trying to map how many
00:54:19.860
of those have had published studies in the scientific literature in terms of their association with cancer
00:54:25.220
risk. And not surprisingly, almost all of them had some published studies associating them with
00:54:32.180
cancer risk. Even the exceptions were probably exceptions because of the way that we searched.
00:54:36.420
For example, we didn't find any study on vanilla, but there were studies on vanillin. So if we had changed
00:54:42.500
with, if we had screened with the names of the biochemical constituents of these ingredients, probably,
00:54:49.460
I guess all of them might have had some studies associating them with cancer risk.
00:54:53.060
How was this paper received by the nutritional epidemiology community?
00:54:58.500
I think it created lots of enemies and lots of friends. And I'm grateful for the enemies who some
00:55:05.460
of them have pushed back with constructive comments. I think that most people realize that we have a
00:55:12.100
problem. I think that even people who disagree with me on nutrition, I have great respect for them. And
00:55:18.820
I'm sure that they're well-intentioned. I think that at the bottom of their heart, it's not that they
00:55:23.940
want to do harm. They want to save lives. They want to improve nutrition. They want to improve our world.
00:55:29.140
So I think that it should be feasible to reach some synthesis of these different approaches and
00:55:36.580
these different trends. And I do see that even people who have used traditional methods do start using
00:55:43.780
some of the methods that we have proposed, for example, these exposure-wide approaches or trying
00:55:49.780
to come up with large consortia and meta-analysis of multiple cohorts to strengthen the results and
00:55:56.980
the standardization of the results. I worry a little bit about some of the transparency of these efforts.
00:56:04.660
To give you one example, I have always argued that if you can have large-scale meta-analysis of
00:56:14.100
multiple teams, ideally all the teams joining forces and publishing a common analysis with common
00:56:20.660
standards, and ideally these would be the best standards and the best statistical tools thrown at
00:56:25.940
the analysis, this is much better than having fragmented publications. So in some questions of
00:56:32.820
nutrition, I have seen that happen, but here's what goes wrong. The invitation goes to other
00:56:40.420
investigators who have already found results that square with the beliefs of the inviting investigator.
00:56:48.980
So there may be 3,000 teams out there and the invitation goes to the 100 teams that have claimed and
00:56:56.820
believe that there is that association. And then these data are cleaned, combined,
00:57:02.580
and analyzed in the way that has found the significant association already, and you have a conclusion
00:57:08.420
with an astronomically low p-value that here it is. We have concluded that our claim for a significant
00:57:14.660
association is indeed true, and here's a large meta-analysis. Now this is equally misleading or even
00:57:21.300
more misleading than the single studies, because you have cherry-picked studies based on what you already know
00:57:29.540
to be the case. And putting them together, you just magnify the cherry-picking, you just solidify the
00:57:36.180
cherry-picking. So one has to be very cautious. Magnitude and amount of evidence alone does not make things
00:57:45.940
better. Actually it can make things worse. You need to ask what is the foundational construct of how that
00:57:53.220
evidence has been generated and identified and synthesized. And in some cases it may be worse
00:58:00.900
than the single small studies that are fragmented, because some of them may not be affected by the
00:58:06.340
same biases. There also seem to be sort of institutional issues around this, right? I mean,
00:58:11.300
your alma mater has a very strong point of view on nutritional epidemiology, right?
00:58:16.420
I think this is unavoidable. There are schools of thought in any scientific field, and Harvard has
00:58:22.740
an amazing team of nutritional epidemiologists. I have great respect for them, even though probably
00:58:28.260
we do not agree on many issues. I think that we should look beyond, let's say, the personal
00:58:35.620
differences or opinion differences. I think that my opinion has less weight
00:58:43.060
than anyone else's weight in that regard. If I want to be true to my standards, I'm not trying
00:58:49.940
to promote something because it is an opinion. What I'm arguing is for better data, for better
00:58:56.500
evidence, for better synthesis, and more unbiased steps in generating the evidence, synthesizing the
00:59:04.500
evidence, and interpreting it. And I'm willing to see whatever result emerges by that process. I'm not
00:59:12.020
committed to any particular result. I would be extremely happy if we do these steps and we
00:59:18.900
come up with a conclusion that, oh, 99% of the nutritional associations that were proposed were
00:59:25.300
actually correct. I have absolutely no problem with that if we do it the right way. What I'm worried is
00:59:32.500
resistance to doing it the right way. I think your point earlier, though, about the difference between,
00:59:39.300
say, how the genetics community and the nutrition community were able to sort of approach this
00:59:45.300
problem, I don't think you can forget your second point, right? Which is, it's very difficult to overcome
00:59:51.300
prior beliefs. And when an individual has made an entire career of a set of beliefs, I think it requires a very
01:00:00.180
special person to be able to say, you know, that may have been incorrect. And that is independent of
01:00:07.380
what that belief is, by the way. That can be a belief that may be correct or may be fundamentally
01:00:14.020
incorrect. You know, it's funny. I recently saw this thing on Netflix. It was the kind of documentary
01:00:20.340
about this DB Cooper case. Do you know this DB Cooper case? It's the only unsolved act of US aviation
01:00:31.300
crime that's never been solved. So do you know this case, John, the guy who hijacked an airplane
01:00:35.940
and then jumped out the back in 1971? Oh, I may have heard of it somewhere,
01:00:40.660
but yeah, I don't recall it very well. Well, it's interesting in that this guy hijacks an airplane
01:00:46.020
with a bomb and requests that the plane be landed while they pick up $200,000 and four parachutes.
01:00:52.100
He then gets the plane to take back off and jumps out the back with the money. And he's never been
01:00:56.740
found. Nine years later, they found a little bit of the money. That's the only real clue. And this
01:01:01.940
documentary focused on four suspects, four of many suspects. And you basically hear the story of each of
01:01:10.020
the four suspects and each of the people who today are making the case for why it was their uncle
01:01:16.500
or their husband or whatever. And my wife and I are watching this and we're thinking it's interesting.
01:01:22.260
And at the end, I just said to her, I said, you know, this is a great
01:01:27.220
sort of example of human nature, which is I believe every one of those people truly believes that it was
01:01:34.820
their relative or friend or whomever who was D.B. Cooper. And yet I think all of them are wrong.
01:01:41.700
I think each of those four suspects is categorically not the person. And yet each of them, I am convinced
01:01:50.900
by their sincerity. And I think that's the problem is I don't think science should be able to be that
01:01:57.940
way. That's the problem I think I have with epidemiology is that I guess I'm just not convinced.
01:02:04.340
It's a science in the way that we talk about science. Well, we have to be cautious because
01:02:10.180
we are human and scientists have beliefs. And I think that there's nothing wrong with having beliefs.
01:02:15.940
I think the issue is, can we map these beliefs? Can we be transparent? Can we be as much restrained
01:02:24.260
about how these beliefs are influencing the contact of our research and the way that we interpret our
01:02:30.340
findings? It will never be perfect. We're not perfect. And I think that aiming to be perfect is
01:02:36.580
not tenable. But at a minimum, we should try to impose as many safeguards in the process as to
01:02:43.380
minimize the chances that we will fool ourselves. You know, not fool others, but fool ourselves to
01:02:48.260
start with us as Feynman would say. This is not easy in fields that have a very deeply entrenched
01:02:55.780
belief system. And I think nutrition is one such. Again, there's no bad intention here. People are
01:03:02.180
well-intentioned. They want to do good. I will open a parenthesis. Of course, there is some bad
01:03:07.060
intentions. There's big food. There's industry who wants to promote their products and sell whatever
01:03:12.660
they produce. And that's a different story. And it is another huge confounder, both in nutrition
01:03:20.420
and in other fields, that we have very high penetrance of financial conflicts. But I think
01:03:27.060
that non-financial conflicts can also be important. And at a minimum, we should try to be transparent
01:03:32.340
about them, try to communicate both to the external world, but also to our own selves,
01:03:39.300
what might be our non-financial conflicts and beliefs in starting to go down a specific path
01:03:47.300
of investigation and a specific interpretation of results. You referred to it very, very briefly
01:03:53.380
earlier. What were the exact details of the case of Brian Wansick at Cornell? That was a lot to do,
01:03:59.620
and it seemed that that went one step further. That seemed like there was something quite deliberate going
01:04:05.220
on. Well, in that case, it was revealed based on the communication of that professor with his students
01:04:11.620
that practically he was urging them to cut corners and to torture the data until they would get some
01:04:19.700
nice-looking result. And practically, he was packaging nice-looking results as soon as they would
01:04:25.940
become available based on that data torturing process. So the data torturing was the central force
01:04:32.740
in generating these dozens of papers that were creating a lot of interest, and probably they
01:04:39.380
were very influential, many of them in terms of decision-making. But if you create results and
01:04:47.300
significance in that fashion, obviously the chances that these would be reproducible results is very,
01:04:53.700
very limited. Yeah. And of course, he was a very prominent person in the field. It makes you wonder,
01:05:00.740
how often is this going on with someone maybe less prominent, where they're part of that 35 million
01:05:07.380
people who are out there authoring the, what are we, about 100,000 papers a month make their way
01:05:13.380
onto PubMed? I mean, it's an avalanche, right? We have a huge production of scientific papers,
01:05:19.380
as you say. And if you look across all sciences, probably we're talking about easily five million
01:05:25.620
papers added every year. And the number is accelerating every single year. Of course,
01:05:31.460
very few of them are both valid and useful. And it's very difficult to sort through all that
01:05:39.460
mountain of published information. I think that research practices are substandard in most scientific
01:05:45.940
fields for most of the research being done. There's a number of surveys that have been conducted
01:05:51.940
asking whether fraud is happening and whether suboptimal research practices are being applied.
01:05:59.620
The results are different depending on whether you ask the person being interviewed on whether they
01:06:04.820
are doing this or whether people in their immediate environment are doing this. So fraud, I think,
01:06:10.660
is uncommon. I don't think that fraud is a common thing in science. It does happen now and then,
01:06:17.300
but I don't think that it is a major threat in terms of the frequency. It is a threat in terms of
01:06:23.140
the visibility that it gets and the damage that it gets to the reputation of science as an enterprise.
01:06:29.380
But it's not common. What is extremely common is questionable research practices or harmful research
01:06:35.620
practices, which means cutting corners in different ways. And depending on how exactly you define that,
01:06:41.940
the percentage of people who might be cutting corners at some point is extremely high. It may be
01:06:46.980
approaching even 100% if you define it very broadly and if you include situations where people are not
01:06:53.300
really cognizant about the damage that they do or the suboptimal character of the approach that they're
01:07:00.340
taking and how it subverts the results and or the conclusions of the study. Now, how do you deal with
01:07:07.780
that? Do you deal with that with putting people away to jail or making them lose their jobs or making them
01:07:13.860
pay $1 million fines? I don't think that that would work because you would probably need to fire the
01:07:20.580
vast majority of the scientific workforce and all of these are good people. They're not there because
01:07:25.300
they're frauds. But you need to work through training, through sensitizing the community, having a
01:07:32.740
grassroots movement about realizing what the problems are, how you can avoid these traps, and how you can use
01:07:40.900
better methods, how you can use better inference tools, and how you can enhance the credibility of
01:07:48.500
your field at large. Not only your own research, but the whole field needs to move to a higher level.
01:07:55.220
And I think that no scientific field is perfect. There are different stages of maturity at different
01:08:01.060
stages of engagement with better methods. And this is happening in a continuous basis. It's an evolution
01:08:08.740
process. So it's not a one time that we did one thing and then science is going to be clean and
01:08:15.860
perfect from now on. It is a continuous struggle. And every day you can do things better or you can do
01:08:21.140
things worse. Of those 35 million people who are out there publishing science today, how many of them
01:08:29.700
do you think are really fit to be principal investigators and be the ones that are making the decisions about where the
01:08:37.140
resources go, what the questions are that should be asked, and what the real and final interpretation
01:08:43.140
is? I mean, that has to be a relatively small fraction of that large number, right?
01:08:47.220
Well, 35 million is the number of author IDs in Scopus. And even that one is a biased estimate,
01:08:55.140
like any estimate. It could be that you have a much, much smaller number of people who are
01:09:01.540
what we call principal investigators. The vast majority of people who have authored at least
01:09:06.340
one scientific paper have just authored a single scientific paper and they have just been co-authors.
01:09:12.020
So they may be students or staff or supporting staff in larger enterprises and they never assume
01:09:19.620
the role of leading research or designing research or being the key players in doing research.
01:09:27.540
There's a much smaller core of people who I would call principal investigators. We're talking probably
01:09:33.620
at a global level, if you take all sciences into account, probably there are less than 1 million.
01:09:38.980
But still, this is a huge number, of course. Their level of training, their level of how familiar
01:09:44.500
they are with best methods, their beliefs and priors and biases, it's very difficult to fathom.
01:09:52.340
Some people argue that we need less research, that probably we should cut back and really be more
01:10:01.780
demanding in asking for credentials and for training and for methodological rigor for people to be able
01:10:09.700
to lead research teams. I'm a bit skeptical about any approach that is starting with a claim we need to
01:10:16.820
cut back on research because I think that research and science eventually is the best thing that has
01:10:23.380
happened to humans. Science is the best thing that has happened to humans. And I think that if we say
01:10:29.060
we need to cut back on research because research is suboptimal, we may end up in a situation where you
01:10:33.460
create an even worse environment, where you have even more limited resources and you still have all
01:10:38.500
these millions of people struggling to get these even more limited resources, which means that they
01:10:44.900
have even more incentives to cut corners, they have even more incentives to come up with strikings,
01:10:49.620
splashing results, and then you have an even more unreliable literature. So less is not necessarily the
01:10:59.140
solution. Actually, it may be problematic. Improved standards, improved circumstances
01:11:06.740
of doing research, an improved environment of doing research is probably what we should struggle for.
01:11:13.540
Creating the background where someone who's really a great scientist and knows what he or she is doing
01:11:22.580
will get support and will be allowed to thrive. Also, allowed to look at things that have a high
01:11:31.860
risk of failing. I think that if we continue incentivizing people to get significant results,
01:11:37.940
no matter how that is defined, we are incentivizing people to do the wrong thing. We should incentivize
01:11:43.700
them to try really interesting ideas and to have a high chance of failing. This is perfectly fine. I think
01:11:51.060
if you don't fail, you're not going to succeed. So we need to be very careful with interventions that
01:11:58.100
happen at a science-wide level or even discipline-wide level. We do not want to destroy science. We want to
01:12:04.900
improve science. And some of the solutions, they run the risk of doing harm sometimes.
01:12:11.860
Based on your comment about the sort of the risk appetite that belongs in science,
01:12:16.980
to me it suggests an important role for philanthropy because industry obviously has a very clear
01:12:24.580
risk appetite that is going to be driven by a financial return. By definition, everybody involved
01:12:30.580
in that is a fiduciary, whether it be to a private or public shareholder. And therefore, it's not the time
01:12:36.500
to take risk for the sake of discovery. Conversely, at the other end of that spectrum,
01:12:41.620
it might seem like the government in the pure public sector should be funding risk. But given the
01:12:50.100
legislative process by which that money is given out and the lack of scientific training that is in
01:12:58.420
the people who are ultimately decision makers for that money, it also seems like a suboptimal place
01:13:05.780
to generate risk. That seems to be the place where you actually want to demonstrate a continued
01:13:12.100
winning career, even if you're not advancing knowledge in the most insightful way. And so
01:13:18.420
what that leaves is an enormous gap for risk, which I think has to be filled with philanthropic work.
01:13:25.620
I agree that philanthropy is very important. No strings attached philanthropy can really be
01:13:32.020
catalytic in generating science that would be very difficult to fund otherwise. Of course,
01:13:38.660
public funding is also essential. And I think that we should make our best to make a convincing case
01:13:44.340
that public funding should increase and not decrease. As I said, decreasing public funding makes things
01:13:49.700
far, far worse for many reasons. I think that we need to realign some of our priorities on what is
01:13:57.700
being funded with each one of these mechanisms. Currently, a lot of public funding is given to generate
01:14:04.740
translational products that are then exploited immediately by companies who make money out of them.
01:14:10.500
And conversely, the testing of these products is paid by the industry. I find that very problematic
01:14:20.180
because the industry is financing and controlling the studies, primarily randomized trials or other types
01:14:27.860
of evaluation research that are judging whether these products that they're making money of are going to be
01:14:35.140
be promoted, used, become blockbusters, and so forth, which inherently has a tremendous conflict.
01:14:43.300
I would argue that the industry should really pay more for the translational research for developing
01:14:48.820
products through the early phases. And then public funding should go to testing whether these products
01:14:56.340
are really worth it, whether they are beneficial, whether they have benefits, whether they have no harms or
01:15:01.460
very limited harms. That research needs to be done with unconflicted funding and unconflicted investigators,
01:15:08.740
ideally through public funds. Of course, philanthropy can also contribute to that.
01:15:13.380
Philanthropy, I think, can play a major role in allowing people to pursue high-risk ideas
01:15:19.620
and things that probably other funders would have a hard time to fund. I think that public funds should
01:15:26.820
also go to high-risk ideas. The public should be informed that science is a very high-risk enterprise.
01:15:32.980
If you try to create a narrative, and I think that this is the traditional narrative that money from
01:15:40.500
taxpayers are used only for paying research grants, that each one of them is delivering
01:15:48.020
some important deliverables. I think this is a false narrative. Most grants, if they really look at
01:15:54.180
interesting questions, they will deliver nothing. Or at least, you know, they will deliver that,
01:15:59.300
sorry, we tried, we spent so much time, we spent so much effort, but we didn't really find something
01:16:04.580
that is interesting. We'll try again. We did our best. We had the best tools. We had the best scientists.
01:16:10.660
We applied the best methods. But we didn't find the new laws of physics. We didn't find a new drug.
01:16:17.860
We didn't find a new diagnostic test. We found nothing. That should be a very valid conclusion.
01:16:23.460
If you do it the right way, with the right tools, with the right methods, with the best scientists
01:16:27.700
being involved, putting down legitimate effort, we should be able to say, we found nothing. But out of
01:16:35.140
one thousand grants, we have five that found something. And that's what makes the difference. It's not that
01:16:41.940
each one of them made a huge contribution. It is these five out of one thousand in some fields and
01:16:47.460
in other fields, obviously, maybe a higher yield that eventually transformed the world.
01:16:52.180
I mean, this seems like a bit of a communications problem because that's clearly the venture
01:16:56.420
capital model that seems to work very well, which is on any given fund, your fund is made back by one
01:17:03.780
company or one bet. It's not an average. It's a very asymmetric bet. And similarly, when you look at
01:17:10.660
other landmark public high-risk funding things, the Manhattan Project, the Space Project,
01:17:16.900
these were upsettingly high-risk projects. And yet I don't get the sense that the public wasn't
01:17:23.380
standing behind those. So it almost seems like there's a disconnect in the way scientists communicate
01:17:28.900
their work to the public versus the way NASA did. I mean, NASA was a PR machine. And obviously,
01:17:34.980
in the case of the Manhattan Project, I think you're in the duress of war. But we can't lose
01:17:40.500
sight of the fact that the scientific community was the one that stood up. The physicists of the
01:17:44.980
day are the ones that said to Roosevelt, like, this has to be done. I mean, Einstein took a stand.
01:17:51.220
So I don't know. I guess it all comes back to scientists need to lead a bit and lead to be
01:17:57.060
better communicators with the public, right? Science communication is a very difficult business.
01:18:02.580
And I think that especially in environments that are polarized, that have lots of conflicts,
01:18:09.380
inherent conflicts, lots of stakeholders in the community are trying to achieve the most for
01:18:15.860
themselves and for their own benefits. It can be very tricky. You know, scientists have a voice,
01:18:22.260
but that voice is often drowned in the middle of all the screams and Twitter and social media and media
01:18:28.260
and agendas and lobbies and everything. How do we strengthen that? I think that
01:18:35.780
there's two paths here. One is to use the same tricks as lobbies do. And the other is to stick to
01:18:41.380
our guns and behave as scientists. You know, we are scientists, we should behave as scientists. I cannot
01:18:47.700
prove that one is better than the other. I think that both myself and many others feel very uneasy
01:18:53.860
when we are told to really cross the borders of science and try to become communicators that are
01:19:01.780
lobbying even for science. It's not easy. You want to avoid exaggeration. You want to say that I don't
01:19:08.900
know. I'm doing research because I don't know. I'm an expert, but I don't know. And this is why I believe
01:19:15.140
that we need to know because these are questions that could make a difference for you. How do you tell
01:19:20.340
people that most likely I will fail, that most likely a hundred people like me will fail, but maybe one
01:19:26.020
will succeed? We need to keep our honesty. We need to make communication clear-cut. We need to also fight
01:19:34.740
against people who are not scientists and who are promising much more. And they would say that,
01:19:39.780
oh, you need to do this because it will be clearly a success. And they're not scientists,
01:19:44.260
but they're very good lobbies. It's very difficult. It's difficult times for science.
01:19:49.860
It's difficult times to defend science. I think that we need to defend our method. We need to defend
01:19:55.300
our principles. We need to defend the honesty of science in trying to communicate it rather than
01:20:02.180
build exaggerated promises or narratives that are not realistic. Then even if we do get the funds,
01:20:11.380
we have just told people lies. I completely agree. I don't think what you and I are saying
01:20:16.180
is mutually exclusive. I think that's the point, right? I mean, you said it a moment ago, right? I
01:20:20.420
mean, Feynman's famous line that, you know, the most important rule in science is not to fool anyone.
01:20:26.420
And that starts with yourself. You're the most, you're the easiest person to fool. And once you
01:20:30.900
fooled yourself, the game is over. And I think the humility that you talk about communicating with
01:20:36.260
the public is the necessary step. I think people, I mean, I guess for me, just having my daughter,
01:20:42.180
who's now just, you know, starting to understand, you know, or ask questions about science is so much
01:20:48.820
fun to be able to talk about this process of discovery and to remind ourselves that it's not
01:20:53.860
innate, right? This is not an innate skill. This is something, this methodology didn't exist 500 years
01:21:01.140
ago. So for all but 0.001% of our genetic lineage, we didn't even have this concept.
01:21:10.180
So that gives us a little bit of empathy for people who have no training, because if you weren't
01:21:16.420
trained in something, you know, it's, you know, there's no chance you're going to understand it
01:21:20.660
without this explanation. But I feel strongly that there can't be a vacuum, right? Because the vacuum
01:21:26.900
always gets filled. And if the scientists aren't the ones speaking, then, you know,
01:21:30.980
if the good scientists aren't the ones speaking, then it's either going to be the bad ones and or
01:21:34.980
the charlatans who will. Before we leave epi, there's one thing I want to go back to that I
01:21:40.420
think is another really interesting paper of yours. This is one from two years ago. This is the challenge
01:21:45.700
of reforming nutritional epidemiologic research. And this is the one where you looked at the single foods
01:21:53.940
foods and the claims that emerged in terms of epidemiology. I mean, some of these things were
01:22:01.160
simply absurd. Do you remember this paper that I'm talking about, John? You've written a couple
01:22:04.940
along these lines, but this is the one that, you know, where you found a publication that suggested
01:22:11.060
eating 12 hazelnuts per day extended life by 12 years, which was the same as drinking three cups of
01:22:19.180
coffee and eating one mandarin orange per day could extend lifespan by five years. Whereas consuming
01:22:26.700
one egg would shorten it by six years and two strips of bacon would shorten life by a decade, which by the
01:22:34.240
way, was more than smoking. How do you explain these results? And more importantly, what does it tell us
01:22:41.300
again about this process? Well, these estimates obviously are tongue in cheek. They're not real
01:22:47.860
estimates. They're a very crude translation of what the average person in the community would get if
01:22:53.700
they see the numbers that are reported, typically with relative risks in the communication of these
01:22:59.540
findings. They're not epidemiologically sound. You know, the true translation to change in life
01:23:06.420
expectancy would be much smaller. But even then, they would probably be too big compared to what the real
01:23:12.900
benefits might be or the real harms might be with these nutrients. I think it just shows the the magnitude
01:23:19.620
of the problem that if you have a system that is so complicated with so inaccurate measurements with so
01:23:24.420
convoluted and overtly correlated variables with selective reporting and biases superimposed, you get a
01:23:34.100
situation pretty much like what we described in the nutrients and cancer risk where
01:23:41.380
you get an implausible big picture where you're talking about huge effects that are unlikely to be true.
01:23:49.220
So it goes back to what we have been discussing about how you remedy that situation, how you bring
01:23:54.980
better methods and better training and better inferences to that land of irreproducible results.
01:24:02.580
Now in, gosh, it might have been 2013, 14, a very interesting study was published called PREDIMED,
01:24:12.180
which we'll spend a minute on. And it was interesting in that it was a clinical trial.
01:24:16.820
It had three arms and it relied on hard outcomes. Hard outcomes meaning mortality or morbidity of some
01:24:24.420
sort rather than just soft outcomes like a biomarker. If you had told me before the results came out,
01:24:33.540
this is the study, you're going to have a low fat arm and two Mediterranean arms that are going to be split
01:24:39.540
this way and this way. And we're going to be looking at primary prevention.
01:24:45.860
I would have said the likelihood you'll see a difference in these three groups is quite low because
01:24:51.460
it just didn't strike me as a very robust design.
01:24:54.900
But I guess to the author's credit, they had selected people that were sick enough that within,
01:25:00.180
you know, I think they had planned to go as long as seven or so years, but under five years,
01:25:04.500
they ended up stopping this study, given that the two arms in the Mediterranean arm,
01:25:09.860
one that was randomized to receive olive oil, the other, I believe, received nuts,
01:25:15.860
performed significantly better than the low fat arm. And that's sort of how the story went until
01:25:25.220
So, here you have a situation where I have to disclose my own bias that I love the Mediterranean
01:25:33.380
diet and I have been a believer that this should be a great diet to use. I mean, I grew up in Athens and
01:25:39.700
obviously, it's something that I enjoy personally a lot. And I would be very happy to see huge benefits
01:25:46.660
with it. For many years, I was touting these results as, here you go, you have a large trial
01:25:52.260
that can show you big benefits on a clinical outcome. And actually, this is Mediterranean diet,
01:25:57.380
which is the diet that I prefer personally, even better.
01:26:00.580
And just to make the point, it was both statistically and clinically very significant.
01:26:06.580
Indeed. Beautiful result. Very nice looking. And I was very, very happy with that. I would use it as
01:26:12.260
an argument that here, here's how you can do it the right way and show clinically relevant results.
01:26:20.420
But then it was realized that, unfortunately, this trial was not really a randomized trial.
01:26:26.020
The randomization had been subverted, that a number of people had not actually been randomized
01:26:30.740
because of problems in the way that they were recruited. And therefore, the data were problematic.
01:26:36.420
You had a design where some of the trial was randomized and some of the trial was actually
01:26:40.980
observational. So, New England Journal of Medicine retracted and republished the study
01:26:46.980
with lots of additional analysis that tried to take care of that subversion of randomization
01:26:53.540
in different ways, excluding these people from the calculations and also using approaches to try to
01:27:01.780
correct for the imposed observational nature of some of the data.
01:27:05.460
The results did not change much, but it creates, of course, a very uneasy feeling that if really the
01:27:13.620
creme de la creme trial, the one that I adored and I admired, had such a major problem, you know, such a
01:27:21.060
major, basic, unbelievably simple problem in its very fundamental structure of how it was run,
01:27:29.700
how much trust can you put on other aspects of the trial that require even more sophistication
01:27:35.700
and even more care? For example, arbitration of outcomes or how you count outcomes. As you say,
01:27:43.140
this is a trial that originally was reported with limited follow-up compared to the original intention.
01:27:47.540
It was stopped at an interim analysis. The trial has had lengthier follow-up. It has published a
01:27:52.980
very large number of papers as secondary analysis, but still we lack what I would like to see as
01:28:01.380
a credible result. I mean, it's a tenuous, partly randomized trial and unfortunately doesn't have the
01:28:08.260
same credibility now compared to what I thought when it was a truly randomized trial and there was one
01:28:15.300
outcome that was reported and that seemed to be very nice. Now, it's a partly randomized, partly subverted
01:28:22.660
trial with, I don't know, 200-300 publications floating around with very different claims each time.
01:28:30.500
Most of them looking very nice but fragmented into that space of secondary analysis.
01:28:37.780
It doesn't mean that Mediterranean diet does not work. I mean, I still like to eat
01:28:42.340
things that fit to a Mediterranean diet and this is my bias, but it just gives one example of how
01:28:50.820
things can go wrong even when you have good intentions. I think that I can see that people
01:28:56.020
really wanted to do it wrong, but one has to be very cautious.
01:28:59.940
Yeah. I mean, I think for me, the takeaway, if I remember some of the details, which I might not,
01:29:05.860
I mean, one of the big issues was the randomization around the inner household subjects,
01:29:09.380
right? They wanted that you couldn't have people in the same house eating the different diets,
01:29:14.500
which is a totally reasonable thought. It just strikes me as sloppiness that it wasn't done
01:29:21.780
correctly in the first place. You know, the cost of doing a study, the cost and duration
01:29:27.620
of doing a study like that is so significant that it's just a shame that on the first go,
01:29:34.100
it's not, you know, it's not nailed because, you know, it could be seven years and a hundred million
01:29:40.020
dollars to do that again. This is true, but one has to take into account that in such an experiment,
01:29:45.860
you have a very large number of people who are involved and their level of methodological training
01:29:51.380
and their ability to understand what needs to be done may vary quite a bit. So it's very difficult
01:29:56.980
to secure that everyone involved in all the sites involved in the trial would do the right thing.
01:30:03.300
And I think that this is an issue also for other randomized trials that are multicenter.
01:30:08.820
Very often now we realize that because of the funding structure, since as we said,
01:30:13.780
there's very little funding from public agencies, most of the multicenter trials are done by the
01:30:19.220
industry. They try to impose some rigor and some standards, but they also have to recruit
01:30:25.860
patients from a very large number of sites, sometimes from countries and from teams
01:30:30.340
that have no expertise in clinical research. And then you can have situations where a lot of the data
01:30:37.540
may not necessarily be fraudulent, but they're collected by people who are not trained, who have
01:30:41.620
no expertise, who don't know what they're doing. And sometimes depending on the study design, especially
01:30:46.660
with unmasked trials or trials that lack allocation concealment or both, you can have severe bias
01:30:54.020
interfere even in studies that seemingly appear to be like the creme de la creme of large scale
01:31:00.980
experimental research. John, let's move on to one last topic, at least for now, which is the events of 2020.
01:31:11.140
In early April, I had this idea talking with someone on my team, which was, boy,
01:31:21.220
the seroprevalence of this thing might be far higher than the confirmed cases of this thing.
01:31:31.540
And if that were true, it would mean that the mortality from this virus is significantly lower
01:31:38.420
than what we believe. This was at a time when I think there was still a widespread belief that
01:31:44.580
five to 10% of people infected with this virus would be killed. And there were basically a nonstop
01:31:53.060
barrage of models suggesting two to 3 million Americans would die of this by the end of the year.
01:32:00.820
The first person I reached out to was David Allison. And I said, hey, David, what do you think
01:32:06.740
about doing an assessment of seropositivity in New York City? And he said, let's call John Ioannidis.
01:32:15.140
So we gave you a call that afternoon. It was a Saturday afternoon. We all hopped on a Zoom and
01:32:19.540
you said, well, guess what? I'm doing this right now in Santa Clara. And I don't think it had been
01:32:25.780
published yet, right? I mean, I think you had just basically got the data, right?
01:32:32.980
Tell me a little bit about that study and what did it show? Because it was certainly one of the
01:32:36.660
first studies to suggest that basically the seropositivity was much higher than the confirmed
01:32:42.340
cases. This is a pair of two studies, actually. One was done in Santa Clara and the other was done in
01:32:48.180
LA County. And both of them, the design aimed to collect a substantial number of participants
01:32:55.140
and tried to see how many of them had antibodies to the virus, which means that they had been
01:33:01.140
infected perhaps at least a couple of weeks ago. And they were studies that Aaron Ben David and Jay
01:33:07.700
Bhattacharya led. And also we had colleagues from the University of Southern California also leading the
01:33:13.940
study in LA County. They were studies that I thought were very important to do. I was just one of many
01:33:21.380
co-investigators, but I feel very proud to have worked with that team. They were very devoted and
01:33:27.060
they really put together in the field an amazing amount of effort and very readily could get some
01:33:33.540
results that would be very useful to tell us more about how widely spread the virus is.
01:33:39.540
The results, I'm not sure whether you would call them surprising, shocking, anticipated. It depends on
01:33:45.380
what your prior would be. Personally, I was open to the possibilities of any result. I had no clue
01:33:51.860
how widely spread the virus would be. And this is why I thought these studies were so essential.
01:33:57.220
I had already published more than a month ago that by that time that we just don't know. We just don't
01:34:03.380
know whether we're talking about a disease that is very widely spread or very limited in its spread,
01:34:09.700
which also translates in an inverse mode to its infection fatality rate. If it's very widely
01:34:15.380
spread, the infection fatality rate per person is much lower. If it is very limited in its spread,
01:34:22.260
it means that fewer people are affected, but the infection fatality rate would be very high. So
01:34:27.620
whatever the answer would be, it would be an interesting answer. And the result was that
01:34:33.300
the virus was very widely spread, far more common compared to what we thought based on the number
01:34:40.260
of tests that we were doing and the number of PCR documented cases at that time. In the early months
01:34:46.340
of the pandemic, we were doing actually very few tests. So it's not surprising at all that the
01:34:51.700
under ascertainment would be huge. I think that once we started doing more tests and or in countries that
01:34:57.620
did more testing, the under ascertainment was different compared to places that were not
01:35:02.580
doing much testing or were doing close to no testing at all. I think that the result was
01:35:09.060
amazing. I felt that that was a very unique moment seeing these results when I first saw that that's
01:35:16.100
what we got, that it was about 50 times more common than we thought based on the documented cases,
01:35:22.580
but obviously generated a lot of attention and a lot of animosity because people had very strong priors.
01:35:27.780
I think it was very unfortunate that all that happened in a situation of a highly polarized,
01:35:33.780
toxic political environment. Somehow people were aligned with different political beliefs
01:35:40.740
as if a political belief should also be aligned with a scientific fact. It was just completely
01:35:48.500
horrible. So it created massive social media and media attention, both good and bad. And I think that
01:35:56.580
we were bombarded with comments both good and bad and criticism. I'm really grateful for the criticism
01:36:02.980
because obviously these were very delicate results that we had to be sure that we had the strongest
01:36:10.020
documentation for what we were saying. And we went through a number of iterations to try to address
01:36:16.740
these criticisms in the best possible way. In the long term, with several months down the road
01:36:22.900
hindsight, we see that these results are practically completely validated. We have now a very large
01:36:29.780
number of seroprevalence studies that have been done in very different places around the world. We see that
01:36:35.620
those studies that were done in early days had, as I said, the worst under ascertainment. We had tremendous
01:36:41.060
under ascertainment in several places around the world. Even in Santa Clara, there's another
01:36:46.180
data set that was included in the national survey of a study that was published in the Lancet about a
01:36:52.020
month ago on hemodialysis patients. And the infection rate, if you translated, that was a couple of
01:36:59.460
months after our study. If you translate it to an infection fatality rate, it's exactly identical to what
01:37:04.420
we had observed in early April. So the study has been validated. It has proven that the virus is a very
01:37:13.460
rapidly and very widely spreading virus, and you need to deal with it based on that profile. It is a virus
01:37:20.020
that can infect huge numbers of people. My estimate is as of early December, probably we may have close
01:37:28.660
to one billion people who have already been infected, you know, more or less around the world.
01:37:34.180
And there's a very steep risk gradient. There's lots of people who have practically no risk or
01:37:41.060
minimal risk of having a bad outcome. And there are some people who have tremendous risk of being
01:37:48.100
devastated. We have, for example, people in nursing homes who have 25% infection fatality rate. You know,
01:37:55.220
one out of four of these people, if they're infected, they will die. So it was one of the most
01:38:01.940
interesting experiences in my career, both of the fascination about seeing these results and also
01:38:08.980
the fascination and some of the intimidation of some of the reaction to these results in a very
01:38:19.620
toxic environment, unfortunately. I don't necessarily mean by name, but what forces were the most critical?
01:38:27.140
Presumably, these would be entities or individuals that wanted to continue to promote the idea that the
01:38:34.020
risk here warranted greater shutdown, slowdown. Help me understand a little bit more where some of the
01:38:40.580
vitriol came from. I think that there were many scientists who made useful comments. And as I said,
01:38:48.100
I'm very grateful for these comments because they helped improve the paper. And then there were
01:38:53.060
many people in social media. That includes some scientists who actually, however, were not epidemiologists.
01:38:59.140
Unfortunately, in the middle of this pandemic, we have seen lots of scientists who have no
01:39:03.860
relationship to epidemiology become kind of Twitter or Facebook epidemiologists all of a sudden and,
01:39:09.700
you know, have very vocal opinions about how things should be done. I remember a scientist who was
01:39:15.780
probably working in physics or not, who was sending emails every two hours to the principal
01:39:21.780
investigator. And I was CC'd in them saying, you have not corrected the paper yet.
01:39:29.460
And every two hours, you know, you have not correct the paper yet. I mean, his comment was wrong to start
01:39:34.420
with. But as we were working on revisions, as you realize, we did that with ultra speed responding
01:39:41.540
within record time to create a revised version and to post it. But even posting, it takes five days,
01:39:48.580
more or less. But what do you think was at the root of this anger directed towards you and the team?
01:39:56.260
Unfortunately, I think that the main reasons were not scientific. I think that most of the animosity
01:40:01.940
was related to the toxic political environment at the moment. And personally, I feel that it is
01:40:07.860
extremely important to to completely dissociate science from politics. Science should be free to
01:40:14.820
say what has been found with all the limitations and all the caveats. But, you know, be precise and
01:40:20.500
accurate. I would never want to think about what a politician is saying in a given time or given
01:40:28.420
circumstances and then modify my findings based on what one politician or another politician is saying.
01:40:33.700
So I think that one of the attacks that I received was that I have conservative ideology,
01:40:42.740
which is like the most stupendous claim that I can think of, you know, looking at my track record and
01:40:50.580
how much I have written about climate change and climate urgency and emergency and the problem with
01:40:57.620
with gun sales and actually, you know, gun sales becoming worse in the environment of the pandemic
01:41:03.140
and the need to promote science and the need to diminish injustice and the need to provide health,
01:41:09.140
good health to all people and to decrease poverty. You know, claiming me that I'm a supporter of
01:41:16.340
conservative ideology, sick conservative ideology is completely weird. And then smearing of all sorts
01:41:23.700
of words that the owner of an airline company had given $5,000 to Stanford, which I was not even aware
01:41:31.460
of. The funding of the trial, which I was not even the PI, was through a crowdsourcing mechanism going
01:41:37.700
to the Stanford Development Office, which I'd never heard of who were the people who had funded that.
01:41:43.060
And of course, none of that money came to me or to all the other investigators who completely volunteered
01:41:48.260
our time. We have received zero dollars for our research, but tons of smearing.
01:41:55.540
Sorry, just to clarify, John, you're saying the accusation was that because an airline had contributed
01:42:02.260
$5,000 to Stanford, for which you saw none of it, that your assessment was really a way to tell everybody
01:42:11.700
that the airlines should be back to flying. Yes. But, you know, I heard about it when the
01:42:18.100
BuzzFeed reporter told me about it. Yeah, yeah, of course. Yeah, yeah, of course. No, no, I get it.
01:42:21.860
I get it. So it's very weird. And, you know, because of all the attacks that we received, you know,
01:42:28.020
I received tons of emails that were hate mail and some of them threatening to me and my family. My mother,
01:42:35.860
she's 86 years old and there was a hoax circulated in social media that she had died of coronavirus and
01:42:43.380
her friends started calling at home to ask when the funeral would be. And when she heard that from
01:42:50.820
multiple friends, she had a life-threatening, hypertensive crisis. So these people really had a
01:42:56.980
very toxic response that did a lot of damage to me and to my family and to others as well. And I think
01:43:05.700
that it was very unfortunate. I asked Stanford to try to find out what was going on. And there was
01:43:12.900
a fact-finding process to try to realize, you know, why is that happening? And of course, it concluded
01:43:18.260
that there was absolutely no conflict of interest and nothing that had gone wrong in terms of any
01:43:23.460
potential conflict of interest. But this doesn't really solve the more major problem. For me, the most
01:43:31.300
major problem is how do we protect scientists? It's not about me. It is about other scientists,
01:43:37.300
some of them even more prominently attacked. I think one example is Tony Fauci. He was my supervisor.
01:43:43.620
I have tremendous respect for him. He was my supervisor when I was at NIH. He's a brilliant
01:43:49.380
scientist and he has been ferociously attacked. There's other scientists who are much younger.
01:43:55.220
They're not, let's say, as powerful. They would be very afraid to disseminate their scientific findings
01:44:01.860
objectively if they have to ponder what the environment is at the moment and what do different
01:44:08.100
politicians say and how will my results be seen. We need to protect those. We need to protect people
01:44:13.860
who would be very much afraid to talk and they would be silenced. If we see examples that, you know,
01:44:20.580
can you see what happened to John Ioannidis or what happened to Tony Fauci? If I were to say something,
01:44:26.820
I would be completely devastated. So I think that we need to be tolerant. We need to give science
01:44:35.460
an opportunity to do its job, to find useful information, to correct mistakes or improve on
01:44:44.740
methods. I mean, this is part of the scientific process, but not really throw all that smearing
01:44:51.700
and all that vicious vitriol to scientists. It's very dangerous, regardless of whether it comes from
01:44:59.140
people in one or another political party or one in another ideology. It ends up being the same. It ends
01:45:05.620
up being populist attacks of the worst possible sort, regardless of whether they come from the left or
01:45:11.780
right or middle or whatever part of the political spectrum. Well, I'm very sorry to hear that you had
01:45:17.380
to go through that, especially at the level of your family. I knew that you had been attacked a little
01:45:23.540
bit. I was not aware that it had spread to the extent that you described it. What do we do going
01:45:29.860
forward here? I mean, it still seems to be a largely partisan issue. There's a very clear left versus
01:45:38.180
right approach to this that seems mostly science agnostic. I think it's viewed as
01:45:49.860
unwise to have a changing opinion outside of science, right? I mean, in science,
01:45:55.140
that's a hallmark of a great thinker, right? Someone who can change their mind in the presence of new
01:46:00.180
information. That's a core competency of doing good science. In fact, much of what we've spoken about
01:46:06.580
today is the toxicity of not being able to update your priors and change your mind in the face of
01:46:12.100
new information. But yet somehow in politics, that is considered the biggest liability of all time.
01:46:18.260
Somehow in politics, anytime you change your mind, it's wishy-washy and you're weak,
01:46:25.060
and you don't know your ideology. There seems to be an incompatibility here. And in a crisis moment like
01:46:31.540
this, which is, this was a crisis, that seems to bring these things to the fore, right?
01:46:38.340
It is true. And I don't want to see that in a negative light necessarily, because somehow the
01:46:44.420
coronavirus crisis has brought science to the limelight in some positive ways. I think that
01:46:50.980
people do discuss more about science. It has become a topic of great interest. People see that their
01:46:57.220
lives depend on science. They feel that their world depends on science. What will happen
01:47:01.940
in the immediate future and mid-range future depends on science and how we interpret science
01:47:06.180
and how we use science. So in a way, suddenly we have had hundreds of millions, if not billions of
01:47:13.620
people become interested in science acutely. But obviously most of those, unfortunately,
01:47:19.940
given our horrible science education, they have no science education. And they use the tools of their
01:47:26.500
traditional society discourse, which is largely political and sectorized to try to deal with
01:47:34.020
scientific questions. And this is an explosive mix. I think it creates a great opportunity to communicate
01:47:41.940
more science and better science. At the same time, it makes science a hostage of all these lobbying
01:47:48.900
forces and all of this turmoil that is happening in the community.
01:47:52.260
Well, John, what are you most optimistic about? I mean, you have lots of time left in your career.
01:47:58.500
You're going to go on and do many more great things. You're going to be a provocateur.
01:48:04.100
What are you most excited and optimistic about in terms of the future of science and the type of work
01:48:10.900
that you're looking to advance? Well, I'm very excited to make sure that, and it does happen,
01:48:16.740
that there's so many things that I don't know. And every day I realize that there's even more things
01:48:21.780
that I don't know. I think that so far, if that continues happening and every day I can find out
01:48:28.660
about more things that I don't know, things that I thought were so, but actually they were wrong and
01:48:33.300
I need to correct them and find ways to correct them, then I really look forward to a good future
01:48:38.900
for science and a good future for humans. I think that we're just at the beginning. We're just at
01:48:44.260
the beginning of knowledge. And I feel like a little kid who just wants to learn a little bit more,
01:48:52.260
a little bit more each time. Well, John, the last time we were together in person,
01:48:56.660
we were in Palo Alto when we had a Mediterranean dinner. So I hope that sometime in 2021, that'll bring
01:49:02.820
us another chance for another flaky white fish and some lemon potatoes and whatever other yummy
01:49:09.300
things we had that evening. That would be wonderful. And I hope that it does increase
01:49:13.860
life expectancy as well. Although even if it doesn't, I think it's worth it. John, thanks so
01:49:20.020
much for your time today. Thank you, Peter. Thank you for listening to this week's episode of The Drive.
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