EP220: Navigating Uncertainty: A Conversation with Dr. Paul Han

Dr. Paul Han on Uncertainty in Medicine and Building Tolerance Through Adaptation

In this episode of The Girl Doc Survival Guide, Christine interviews Dr. Paul Han, an NIH Senior Scientist specializing in risk communication, medical decision-making, and uncertainty in healthcare, whose career shifted from general internal medicine and palliative care to research via an NCI cancer prevention fellowship. Han shares that persistent “gray zone” questions in primary and end-of-life care, plus personal circumstances like spousal support and financial stability, enabled his mid-career leap into the unknown. He explains uncertainty as two-sided: something healthcare tries to reduce but also a necessary source of curiosity for clinicians and hope for patients, especially in serious illness. Han connects uncertainty to cognitive biases as flawed attempts to regain certainty, and reframes “uncertainty tolerance” from merely enduring anxiety to situation-specific adaptation, emphasizing virtues such as humility, flexibility, and courage; he also notes his own recent prostate cancer diagnosis.

00:00 Meet Dr Paul Han

01:31 Midcareer Leap to Research

03:58 Drawn to Gray Zones

04:40 What Enables a Big Switch

06:48 Uncertainty as Friend and Foe

11:15 Why Uncertainty Feels Scary

13:48 Biases Born From Uncertainty

15:37 Rethinking Uncertainty Tolerance

18:32 Virtues for Adaptive Care

21:15 Letting Go of Outcomes

23:22 Closing Thoughts

Transcript

Christine Ko: [00:00:00] Welcome back to The Girl Doc Survival Guide. Today I'm very pleased to be with Dr. Paul Han. Paul Han, MD, MA, MPH, is a Senior Scientist in the Behavioral Research Program at NIH, whose work focuses on risk communication, medical decision-making, and the management of uncertainty in healthcare. His research spans cancer prevention and treatment, genomic medicine, and palliative and end-of-life care, with an emphasis on improving how patients and clinicians communicate and manage uncertainty. Dr. Han earned his MD from New York University School of Medicine, as well as an MA in Bioethics and an MPH from University of Pittsburgh, and completed residency training at University of California Los Angeles. After practicing as a general internist and palliative medicine physician, he completed an NCI Cancer Prevention Fellowship and transitioned to a research-focused career. He is the author of Uncertainty in Medicine: A Framework for [00:01:00] Tolerance, and has published more than 200 peer-reviewed papers while leading various initiatives on risk communication, shared decision-making, and uncertainty management in healthcare. Welcome to Paul. 

Paul Han: Thank you very much. It's great to participate today.

Christine Ko: I find your career so interesting that you transitioned to do this cancer prevention fellowship and research focus in this part of your career. Either related to that or something else, can you first share a personal anecdote?

Paul Han: Yeah, sure. This was a mid-career transition for me to go into research and to devote my career to studying medical uncertainty. I started my career in clinical practice and did some medical education but mostly practiced as a general internist and then as a palliative medicine physician. All along, I found myself, in clinical practice wanting to get underneath this problem of uncertainty that I was really running into at [00:02:00] every turn doing primary care, taking care of patients with a broad spectrum of medical problems. When I shifted to palliative medicine, a lot of these sort of uncertainties were magnified in taking care of critically ill patients with advanced illness, dealing with end-of-life issues. I found myself really wanting to understand this experience of uncertainty that I was feeling and that my patients were feeling in many different ways. I can remember turning 40 and thinking about what I wanted to do with the rest of my career and feeling pretty much entrenched. I could keep doing this for years and years, but I still had these nagging questions about this experience of uncertainty I was running into and wanting to understand that a little bit better. I remember going out to dinner with my wife to celebrate my 40th birthday, and just thinking, I could keep doing this, but I wanted to go in a different direction. So I found out about this research fellowship that really focused on ethical issues in cancer [00:03:00] prevention and kind of more broadly in medicine and public health. And so I decided to just go for it, leave a stable career, and move into a new direction. That really changed my professional life for sure, maybe my personal life as well, and led me on a kind of very different journey. 

Christine Ko: Yeah. I really respect that, and I find that fascinating. Because training in medical fields is so long, 'cause of sunk costs, people don't really switch, even if actually they're relatively unhappy with what they do.

Paul Han: Yeah, it's true. You put so much into it, and then you get into an autopilot mode, with your career. And medicine's hard, keeping up and learning and trying to be an excellent physician. It's demanding, on your time. And it was easy for me, I remember, to just come home after a long day and just turn my brain off and just relax or whatever.

But I had these nagging questions. I was always attracted to gray [00:04:00] zones, whether it was in primary care practice or a lot of palliative medicine and end of life is inherently gray. End of life care. I was just attracted to these sort of medical controversies when med experts didn't agree or when the evidence wasn't sufficient and what you do in those cases. So I ended up actually doing a Master's in Bioethics along the way on my own time. It took me six years taking one course per semester, trying to delve into these issues. It finally got to the point I felt like I needed to do something to look at things more intensively and to really devote thought to be really satisfied. So that made me go against the inertia of continuing with the same kind of career path. 

Christine Ko: Is it just maybe inherent to your personality that you could make a switch like that? Or do you think that there's something that's useful or necessary if someone's considering doing something like what you did?

Paul Han: That's a really good question. I think it's so individual. So for me, I [00:05:00] must point to the fact that I, first of all, had a very supportive spouse. And I had financial stability and felt like I could make a change and go on a fellow's salary for a couple years. There's all those interpersonal kinds of things that are variable for people. I also felt like I really had this sort of attraction to uncertainty, even going back before medical training. I was a religious studies major in college, and I was always attracted then to these questions of meaning and so forth. And so I feel like some of this was even deeper than medicine for me to be attracted to this topic of uncertainty. All these things, plus my clinical experiences, and I had the luxury to actually make a move as well, whereas, had I not had that kind of family support and everything else, then maybe it wouldn't have happened, for me too. So in some sense, I feel lucky. 

Christine Ko: Yeah. I'm glad you brought that up because it's true that a decision like that you do have to have [00:06:00] the privilege as you mentioned, of having financial stability in order to not totally disrupt your life. Also, to accept earning less, I think, is something that's a challenge. Even if you're stable, a lot of people aren't willing to do that. I think the gut reaction is, "No, I don't wanna earn less." But anyway, that's amazing that you did that.

Paul Han: Thanks. And I'll just add one thing is that it's a leap into the unknown. Our subject is uncertainty. On a personal and professional level I realized on that fateful 40th birthday dinner, that it was just this decision that I was gonna really move into the unknown. And in, in some ways, it felt worth it, but it's a leap of faith, you know. Always with uncertainty. 

Christine Ko: Yes, that's a good point. You were actually really living the subject you would be studying. Since you've had this experience of being a doctor, seeing patients, talking to them about, a prognosis that is uncertain, and then you [00:07:00] studied it, and have been studying it more from a research, sort of thought side, what do you think that it would be good for all patients and doctors to understand about uncertainty, in general, and uncertainty as related to medicine?

Paul Han: Yeah. That's such a huge question. There are many things to say about that. If I was to boil things down into one sort of theme, it's that really uncertainty, whether it's in our daily lives, outside of healthcare, outside of medicine, or within the practice of medicine, or for patients experiencing illness and uncertainty related to illness, that uncertainty really is a two-sided phenomenon of human experience. On the one hand, it's something that we generally try to avoid or reduce and eliminate when we can. And in fact, all of healthcare, you could argue, is really geared towards [00:08:00] reducing or eliminating uncertainty whenever possible. And that's the mode of most of human life too. We go around living our lives trying to become more certain about what we're doing and about our actions and making sure that we're certain that our actions are the best possible sort of response to a situation. And so in some ways, the uncertainty part of it, it's the thing we're getting rid of.

It's our worst enemy in some sense. And I think medical training really promotes that kind of view. And yet, on the other hand, I think both in our everyday lives and in medicine uncertainty is actually a good thing in many ways. So it's not only our worst enemy it's our best friend and companion in some ways, and we need uncertainty actually to live meaningful lives, I think.

If we knew, and people have written about this, but if we knew everything that was gonna happen in the future, our ultimate fates and the consequences [00:09:00] of every decision, then there wouldn't be much to live for, right? If there was no uncertainties to challenge us and to make us curious and to make us want to move ahead and to meet challenges.

In medicine it's the same way. It plays out perhaps a little bit differently, but for the clinician, uncertainty is a really necessary experience and capacity because it really stimulates our curiosity. It makes us open-minded as clinicians and flexible, and so that we don't rule out any opportunities for learning or to seeing if things go a different way.

And we have to have that uncertainty to make us open and not dogmatic. And for patients, what I've seen and particularly in the context of advanced serious life-limiting illnesses or at the end of life, is that uncertainty is really essential for hope. And the people who have advanced illness, they like big confidence intervals. They like the [00:10:00] fact that research is still ongoing because this opens up the possibility at least of a desired outcome and everybody wants to get better. And, cancer patients or anyone with a serious diagnosis wants possibilities, for treatment and for cure and for living longer.

And it's the uncertainty, the fact that we don't know about any particular treatment that is actually again, both a negative, but also an essential positive because it leaves open that space for hope. And so uncertainty is so two-sided. In some sense we can't live without it, on the one hand, 'cause there's positive effects. And we can't live with it either because there's obviously negative effects. It makes us, feel pessimistic or fearful or indecisive. And so those are all kind of natural reactions or natural psychological reactions that we can't help ourselves but feel that way, and we all want certainty. But we have to recognize that there's two sides of this coin, [00:11:00] and we also need uncertainty to live.

So, it boils down to how do we balance that, and how do we actually tolerate our uncertainty? And that's a big focus of my work in recent years, understanding what it means to tolerate uncertainty. 

Christine Ko: Yeah. Do you have insights into that, how we tolerate it better? Why does it make us so uncomfortable? Why can't we just accept it for the positives that it gives us? 

Paul Han: That's also a huge topic. It's pretty well known and documented in the psychological literature how uncertainty is the fear of the unknown. A colleague of mine, Nicholas Carlton, calls this the mother of all fears. Uncertainty is inherently fearful, aversive, and psychologically negative for us, possibly for evolutionary reasons. Maybe all creatures on Earth are evolved to at least take a defensive posture towards uncertainty because it's protective and adaptive. It keeps us from jumping off a [00:12:00] cliff or doing things that are that are not adaptive to our survival, to be cautious and careful and in this defensive posture. So it's probably hardwired into us to some extent. The part of uncertainty that is aversive is when we imagine the future outcome that we're uncertain about to be the worst. And so that provokes fear. And there's been a lot of work too that shows that people differ. This is also a personality difference among people, whether you tend to see the worst or the best. There's optimists and pessimists, for example, when you talk about future expectations. And so some of this is variable on an individual level as well. But I think that overall we're probably hardwired to be like this from an evolutionary standpoint, and there's a lot of work that sort of suggests this as well.

But I think it's not only biological, but also cultural. Certain professions, like in medicine, reinforce this sort of aversion to uncertainty, and for good reason. I [00:13:00] think it's adaptive also. To be highly functioning, excellent physicians, we need to be averse to negative outcomes of uncertainty, and we need to think about the worst. What if I did this? What's gonna happen to the patient? We need to prevent those worst case scenarios. So this becomes culturally, within the culture of medicine, reinforced, and in our overall society as well. And so I would say that most of the time, this is a very adaptive response. Where it gets maladaptive is number one, when we forget about the positive aspects of uncertainty, and that we actually need uncertainty to shock us out of this sort of one track obsession with obtaining certainty. We need to look inwards on our subjective experience of it, and how we can tolerate it better.

Christine Ko: When you mention this fear of uncertainty is probably hardwired into us, that reminds me of cognitive bias in general, in the sense of how our minds work, that it seems like a lot [00:14:00] of the cognitive biases that we have are also hardwired into us. I guess uncertainty, maybe, relates to cognitive bias in a certain way? 

Paul Han: Yeah, I think it does. Biases come in many different flavors, but at the root of all of them probably is these imperfect attempts to deal with uncertainty. So uncertainty opens the way for cognitive biases 'cause these biases are just simply our responses to uncertainty. Unfortunately, they can be deeply flawed because they reflect, our cognitive limitations, the limitations of the human brain, for example. But some of them are cultural as well. Again, these biases can be culturally constructed, and we tend to reinforce them when we engage in certain kinds of thinking and responses to uncertainty, and we don't reexamine those or look at them critically. We just perpetuate these sort of biased ways of looking [00:15:00] at things. For example, people being surprised when somebody gets lung cancer and they're not a smoker, saying, "How did you get lung cancer?" Because we fall back on these very simplistic mental explanatory models of the world, which you can look at as a cognitive bias too, because we're reaching for an easy black-and-white explanation that fits, that makes us comfortable and helps us deny that true uncertainty actually exists. These are all manifestations of our fallible and flawed attempts to deal with our uncertainty, and these various kind of biases are things we need to more critically examine. 

Christine Ko: Yeah. You've written a book, Uncertainty in Medicine: A Framework for Tolerance, and you just mentioned that, to become more tolerant of uncertainty. How can we do that? 

Paul Han: Yeah. I have to admit my uncertainty about this because I don't have the answers, but I've been thinking about this question from a lot of different angles for a while. And what I actually [00:16:00] believe goes against a conventional understanding of uncertainty tolerance. That term's been used for decades in, social science research, and it's used even just in common speech. People talk a lot about uncertainty tolerance, risk tolerance, et cetera. And if you look at the dominant literature on this, it really equates or defines uncertainty tolerance as the ability to simply endure uncertainty. It frames uncertainty as exclusively negative, psychologically aversive, and it measures and conceptualizes uncertainty in terms of the absence of those negative responses to uncertainty. So you are intolerant of uncertainty if you become pessimistic, fearful, and indecisive in response to uncertainty or in uncertain situations. And you are tolerant if you are not pessimistic, fearful, or indecisive. So you're able to make a decision and feel good about it and have no anxiety, and I [00:17:00] think we need to get beyond that view of uncertainty tolerance.

My thinking has evolved on this. It has nothing to do with those conventional responses. Sometimes being fearful and indecisive is exactly a good response to uncertainty. And so we should get away from thinking of tolerance as the absence of those sort of problems. And we need to think more broadly of tolerance in terms of our ability to adapt to situations and to enact a response or set of responses to uncertainty that is appropriate to me as an individual and to the specific situation that I'm in. What's difficult if you adopt this way of thinking is that it requires uncertainty tolerance to even believe in this definition, because it means that there is no one right answer. And this goes against what we're taught in medical school. An adaptive uncertainty tolerance response might be to choose that treatment that we as [00:18:00] the doctors think is not the right thing. There's a psychologist, Louis Tay, who calls this situation-specific optimality, that we have to look for what's optimal in that situation for me as an individual in my peculiar, unique situation. That is not in any textbook, right? Every life is unique. And so it's unsatisfying in a certain way when we like clinical guidelines and we like black-and-white answers, but this is a way I think of thinking about uncertainty tolerance that I think is more appropriate. The further implication of this means that we need to focus not solely on what's the right outcome or even what's the right process or action to take. Like, what should we put in the clinical guideline? It's not only what we should do and what we should achieve, but it's actually how we should be as people. And so I've gotten very interested in recent years in what philosophers [00:19:00] call virtues. Psychologists call these character strengths, but things like virtues, like humility and flexibility and courage, these sort of virtues that help people, help us to know how to be and how to live our lives.

So it's more a focus on how we should be than what we should do and what we should achieve. And it's not to say we should forget about maximizing patient outcomes or following guidelines. But we also have to realize that those will only get us so far, and that we actually have to think about these capacities or virtues and what we should cultivate in ourselves as people and as doctors to actually be able to adapt to uncertainty.

Christine Ko: That's helpful. You've moved towards thinking tolerance of uncertainty is an ability to adapt rather than just endure. Be able to adapt to the fact that it exists and recognize the positive as well as the negative. And you said it then [00:20:00] moves into a question of how we should be. So say in medicine, a lot of times we're focused on the outcome, the future. And the best outcome is you're cured of disease. It's all gone. But the fact is that we can't, yet, and I don't think for years we'll be able to eradicate all diseases. Yes, we want that ideal outcome when we can cure someone of their disease. In a way, the more important thing, like you were saying, is how actually can I maybe get you to be able to live exactly the life you want while still having this disease? I definitely want my patients to have the best outcome possible and cure them of disease if possible. 

Paul Han: Yeah. When we focus solely on outcomes, I'm not denigrating that. That's what we should do as clinicians. We want the best outcome for all of our patients, and patients want to be cured, and they want to get better and feel better. That's why they're seeing us. There's nothing wrong with focusing on that outcome. But I think that what's wrong or less optimal is if that's the only outcome that we're focused [00:21:00] on. And I think that you're completely right that there are gonna be cases that we can't cure and successfully manage by our medical or biomedical criteria. We didn't make the disease go away, or we didn't ameliorate it completely.

I was diagnosed with prostate cancer last year, so I faced this as a patient as well. We definitely want to optimize the outcome as patients and clinicians, but we have to be prepared if that outcome is not achieved, and we have to, in some sense, let go of the outcome. So the decision to have a treatment or not, or have treatment A or B, we deliberate, we do the best we can based on all the evidence that's available, and this is whether you're on the doctor side or the patient side. But at some point when you make the decision, then you have to let go of the outcomes, and you have to just be able to have the presence of mind and of spirit to move forward no matter what, and to [00:22:00] tell yourself that no matter what happens, I'm gonna be fine and I'm gonna adapt.

That's the greatest service we can give to our patients, to help them to adapt no matter what happens, no matter what the outcome, and I think that is what uncertainty tolerance is about. It's not saying, if I don't have the successful outcome I want, then I'm finished. I might as well die. It is actually that power of adaptation, that capacity to adapt no matter what the outcome is. We do our very best, and I think clinicians have to practice that way. Do your best, bring the best evidence to bear, make the best decision free of cognitive biases as much as possible, but then what? We're gonna get through this, and I'm gonna help you as a physician. And on the patient side, I'm gonna deal with this no matter what, because I have the power to adapt. And I think the way to nurture that power is to cultivate these character strengths or virtues, or [00:23:00] capacities, whatever you wanna call it, because again, that focus is on getting us in the right frame of mind and spirit to be humble, to be flexible, to be able to adapt and to be courageous, to move forward. That's why I identify those three virtues in particular as being important to really adapt no matter what the outcome, no matter what happens. 

Christine Ko: I like it. Do you have any final thoughts? 

Paul Han: No. This has been enjoyable talking to you, and thanks for the opportunity. 

Christine Ko: Thank you so much.