Why Most People Shrug Off the Biggest Threat to Their Health 
 
Here’s a number that should keep you up at night: approximately 800,000 Americans are seriously harmed by diagnostic errors every single year (Newman-Toker et al., BMJ Quality & Safety , 2024). That’s more people than live in San Francisco. Almost one in four Americans has been personally affected by a misdiagnosis, or watched it happen to someone they love (IHI/NPSF & NORC, 2017). The Institute of Medicine concluded that most people will experience at least one diagnostic error in their lifetime (National Academies of Sciences, Engineering, and Medicine, 2015). 
 
And yet (here’s the wild part) most of us walk into a doctor’s office and never once think, “Could they get this wrong?” 
 
Why? Why do we worry more about plane crashes (roughly 1 in 11 million chance) than about the doctor sitting three feet away misreading our symptoms? The answer lies in our own brains, and it’s both fascinating and deeply frustrating. 

Your Brain Is Lying to You (Nicely) 

 Psychologists have known about a quirk in human thinking since 1980, when researcher Neil Weinstein published a landmark study in the Journal of Personality and Social Psychology. He asked college students to compare their chances of experiencing negative events (health problems, divorces, drinking problems) to those of their classmates. The result? The overwhelming majority believed bad things were less likely to happen to them than to everyone else. Weinstein called this “unrealistic optimism,” and in over four decades of follow-up research, it has proven to be one of the most stubborn biases the human brain produces. 
 
This isn’t a rare glitch. Studies show that roughly 80% of people display optimistic bias. It crosses every culture, gender, ethnicity, and age group (Shepperd, Klein, et al., A Primer on Unrealistic Optimism, Current Directions in Psychological Science, 2015). When it comes to health risks specifically, Weinstein’s 1982 follow-up study in the Journal of Behavioral Medicine found that people showed significant optimistic bias for 34 out of 45 health threats. They consistently believed their own chances of getting sick were below average, which, mathematically, cannot be true for most people in a group. 
 
Think about that for a second. We know misdiagnosis is common. We know the statistics. But our brains whisper, “Sure, it happens, but not to me.” 
 
This bias is especially strong for health problems people believe they can control or that haven’t happened to them yet. As Weinstein’s 1987 community-wide study demonstrated, people tend to reason that if a problem hasn’t appeared so far, it’s unlikely to show up in the future, even when this reasoning is flat-out wrong. Diagnostic errors don’t care about your track record. They can strike anyone, anytime, regardless of how healthy you’ve been. 

The “Doctor Knows Best” Trap 

There’s a second psychological force at work, and it’s even harder to fight: authority bias. Most of us grew up in a world where doctors were the ultimate experts. You got sick, you went to the doctor, they told you what was wrong, and you took the medicine. End of story. 
 
This top-down model of medicine, where the doctor does things to you rather than works with you, has deep roots. Since the beginning of medicine, as the source document notes, “healthcare has been applied to the patient. Healers, physicians, and surgeons used their skills to fix what was deemed wrong with the patient’s body or mind.” Patients had no access to the expert’s knowledge. And while medicine has evolved, this power dynamic hasn’t fully disappeared. 
 
The result? Many patients follow medical advice strictly out of compliance rather than genuine understanding. Research shows that some patients view medical interventions as something done to them rather than a collaborative process (Hovey et al., Quality and Safety in Health Care, 2010; Eriksen et al., Journal of Clinical Nursing, 2023). They may be highly compliant (showing up for appointments, taking their pills) while simultaneously lacking the confidence or encouragement to speak up and say, “Wait, I’m not sure this diagnosis makes sense.” 
 
And here’s the kicker: the system itself reinforces this silence. Studies show that clinicians interrupt patients after an average of just 11 seconds (Singh Ospina et al., Journal of General Internal Medicine, 2019). Eleven seconds. That’s barely enough time to say, “I’ve been having this pain in my…” before the doctor is already steering the conversation. 
 

Why Thinking “It Won’t Happen to Me” Is Dangerous 

 
Unrealistic optimism isn’t just an amusing psychological curiosity. It’s genuinely dangerous. Dr. Tali Sharot, a leading neuroscientist studying this bias, has noted that underestimating risk reduces precautionary behavior: people skip screenings, ignore warning signs, and don’t push back on diagnoses that don’t feel right. One study found that smokers were more than twice as likely as nonsmokers to doubt they would die from smoking, even after years of the habit (Ethics Unwrapped, University of Texas at Austin, 2022). 
 
The same psychology applies to diagnosis. If you believe you are somehow less likely than others to be misdiagnosed, you are less likely to: 
 
– Prepare a list of symptoms before a doctor’s visit 
– Ask questions about your diagnosis 
– Seek a second opinion when something feels off 
– Follow up on test results or next steps 
– Track your own health information over time 
 
In public health research, people who underestimate their comparative risk of heart disease tend to know less about the condition and remain less concerned even after reading informative materials (Wikipedia, “Optimism bias,” citing Weinstein and others). The parallel to misdiagnosis is direct: people who don’t believe it can happen to them won’t take the steps to prevent it. 
 

The Communication Breakdown That Makes Everything Worse 

If optimism bias is the match, our fractured healthcare system is the gasoline. Poor communication between patients and clinicians is a factor in up to 78% of diagnostic errors in primary care settings (Singh et al., JAMA Internal Medicine, 2013). As a recent AHRQ report outlined, diagnostic errors stem from a tangle of communication challenges, inadequate history taking, incomplete physical examinations, and issues of clinical cognition and implicit bias, all occurring within a fragmented and difficult-to-navigate healthcare system (Khan et al., AHRQ, 2024). 
 
Sir William Osler, the 19th-century physician who cofounded Johns Hopkins Hospital, nailed it over a century ago: “Listen to your patient; he is telling you the diagnosis” (Silverman et al., The Quotable Osler, 2007). But health system pressures have truncated the time available for a primary care visit. There’s less time for a thorough history, less time for a complete exam, and a growing reliance on expensive diagnostic tests that may or may not point in the right direction. The opportunity for real conversation, the kind where a patient fully explains their symptoms and a clinician truly listens, has been squeezed nearly out of existence (Freedman et al., Journal of Health Economics, 2021; Linzer et al., Journal of General Internal Medicine, 2015). 
 

You Are the Only Constant in Your Healthcare 

 
Here is a truth that most people never stop to consider: you are the only person present for every single step of your diagnostic journey. Your primary care doctor sees you for a few minutes. The specialist sees a piece of the puzzle. The lab tech processes a number. The radiologist reads an image. But you? You are there from the very first moment you notice something is wrong through every referral, every test, every follow-up, and every outcome. 
 
You are also the only one who knows for certain whether the medical process, the teamwork, and the professional expertise have actually resulted in an accurate, timely, and clearly communicated diagnosis. And you are the one who must live with the consequences if they haven’t. 
 
This is why the National Academy of Medicine’s 2015 report on diagnostic error called improving diagnosis “a moral, professional, and public health imperative” (NASEM, Improving Diagnosis in Health Care, 2015). And it’s why patient engagement isn’t a nice-to-have. It’s a survival skill. 
 

So What Actually Works? How Do I Wake People Up? 

 
If simply telling people about the risks of misdiagnosis isn’t enough (and it isn’t, because optimism bias resists education), what does work? 
 

1. Make it personal and relatable. 
    
   
   

   Weinstein’s research found that unrealistic optimism decreases when people have personal experience with a negative event or when they learn concrete details about what happened to people like them (Weinstein, Journal of Behavioral Medicine, 1987). Patient stories aren’t just emotional window dressing. They are one of the most powerful tools for puncturing the “it won’t happen to me” bubble. Research published in Health Affairs found that collecting and sharing patient narratives about diagnostic errors provides unique, valuable insight that formal reporting systems often miss (Giardina et al., Health Affairs, 2018). 
    

2. Build skills, not just awareness. 

   
    
   A growing body of evidence shows that patient activation (the skills, knowledge, and confidence that equip patients to manage their own healthcare) leads to better health outcomes and care experiences (Hibbard et al., Health Affairs, 2013). Critically, research shows that patients who start at the lowest activation levels tend to improve the most when given tailored support. This means the biggest gains come from helping the people who currently feel the least empowered. 
    

3. Give patients practical tools. 

   
    
   An environmental scan identified more than 300 versions of “questions to ask your doctor” tools, organized by medical condition and specialty (Hill et al., Joint Commission Journal on Quality and Patient Safety, forthcoming). AHRQ’s Toolkit for Engaging Patients in Diagnostic Safety provides strategies to help patients and clinicians bridge the communication divide. The Pulse Center for Patient Safety Education and Advocacy runs a TakeCHARGE Campaign that teaches patients five concrete steps: keep your medical history handy, prepare for appointments, make a list of questions, bring a friend or family member, and follow up on results. 
    
   These aren’t complicated ideas. But they work because they shift patients from passive recipients to active participants. 
    

4. Leverage the power of peers. 

   
    
   An experiment published in Applied Psychology: Health and Well-Being (Dolinski et al., 2022) found that unrealistic optimism could be reduced when participants read articles showing that other people, their peers, were actively engaging in health-protective behaviors. When people see that others like them are taking action, the “it won’t happen to me” shield weakens. Community-based patient organizations like LymeDisease.org and the Patient-Led Research Collaborative have demonstrated this effect in the real world, with patients educating and activating other patients. 
    

5. Close the communication loop. 

   
    
   The ideal form of medical communication is bidirectional, collaborative, and closed-loop (Smith et al., AHRQ, 2017). That means a respectful back-and-forth between patient and provider, a continual exchange of information, and, crucially, checking for comprehension. A person has not actually communicated a diagnosis until they’ve confirmed that the patient understands it. If nothing else from this article sticks, remember this: if your doctor can’t explain your diagnosis in words you understand, the diagnostic process is not finished.  
    

   
   The People Changing the Game 
   
   

    
   Perhaps the most encouraging development is the rise of patient-led initiatives that are proving patients aren’t just stakeholders in the diagnostic process. They can be leaders. 
    
   The Patient-Led Research Collaborative, a group of patients with long COVID, designed, funded, and conducted the first research on long COVID in April 2020, before most of the medical establishment had even acknowledged the condition existed. They have since published scientific papers and created a $5 million fund for biomedical research. 
    
   As cofounder Lisa McCorkell told the National Academies: “It’s not enough just to have a patient in a room. Their voice needs to matter in that room, their expertise needs to be valued, their insights need to be incorporated.” 
    
   LymeDisease.org began as a patient education effort and evolved into the largest study of Lyme disease diagnosis and treatment ever conducted, enrolling over 16,000 patients. 
    
   These organizations didn’t wait for the healthcare system to invite them in. They built the door themselves. 
    

   
   What You Can Do Tomorrow Morning 
   
   

    
   You don’t need to start a research organization or lobby Congress to protect yourself. You need to fight your own optimism bias. Here’s how: 
    
   Accept that misdiagnosis can happen to you. Not because you’re unlucky, but because you’re a human being using a healthcare system that produces diagnostic errors at a startlingly high rate. The math doesn’t care about your optimism. 
    
   Prepare for every appointment. Write down your symptoms: when they started, what makes them better or worse, what you’ve already tried. Bring a family member or friend to help you remember what the doctor says and to advocate for you if needed (AAFP, American Family Physician, 2011; Kausar et al., Journal of Family Medicine and Primary Care, 2013). 
    
   Ask questions. Ask what your diagnosis is. Ask what else it could be. Ask what happens next and when you should expect results. Ask what you should do if you don’t get better. These questions aren’t rude. They’re the bare minimum of a safe diagnostic process. 
    
   Follow up. Do not assume that no news is good news. Research consistently shows that missed test results and failed follow-ups are among the most common breakdowns in the diagnostic process. 
    
   Trust your instincts. If something doesn’t feel right, say so. If you’re not getting better on the prescribed treatment, go back. If you feel dismissed, seek another opinion. The data shows that patients with conditions that are difficult to diagnose (rare diseases, endometriosis, sepsis, long COVID) are often the most activated advocates for their own care, precisely because they’ve learned the hard way that the system doesn’t always get it right the first time. 
    

Or you can just use Medome, www.medome.ai, developed for this purpose. 
 

The Bottom Line 

 
Diagnosis is a team sport, and right now, the most important player (you) might be sitting on the bench because your brain told you the game was already won. It wasn’t. The science is clear: we are wired to underestimate our own risk, overtrust authority, and assume that bad outcomes happen to other people. These biases are universal, powerful, and, if left unchecked, potentially devastating. 
 
But they are not unbeatable. Every time you prepare for an appointment, ask a question, push back on something that doesn’t feel right, or follow up on a test result, you are fighting back against the psychological forces that keep patients passive. You are doing the work that no doctor, no algorithm, and no healthcare system can do for you. 
 
Because in the end, the only person who will be there for every single step of your diagnostic journey is you. Make sure you’re paying attention. 
 

References 

 
– Bell SK, Dong J, Ngo L, et al. Diagnostic error experiences of patients and families with limited English-language health literacy. BMJ Quality & Safety. 2023;32(11):644-654. 
– Dolinski D, et al. Media intervention program for reducing unrealistic optimism bias. Applied Psychology: Health and Well-Being. 2022. 
– Eriksen AA, Fegran L, Fredwall TE, Larsen IB. Patients’ negative experiences with health care settings. Journal of Clinical Nursing. 2023;32(17-18):5816-5835. 
– Freedman S, Golberstein E, Huang TY, et al. Docs with their eyes on the clock? Journal of Health Economics. 2021;77:102442. 
– Giardina TD, Haskell H, Menon S, et al. Learning from patients’ experiences related to diagnostic errors. Health Affairs. 2018;37:1821-1827. 
– Hibbard JH, Greene J. What the evidence shows about patient activation. Health Affairs. 2013;32(2):207-214. 
– Hill M, Coppinger T, Sedig K, et al. Asking questions to improve diagnostic safety: a scoping review. Joint Commission Journal on Quality and Patient Safety. Forthcoming. 
– Hovey RB, Morck A, Nettleton S, et al. Partners in our care: patient safety from a patient perspective. Quality and Safety in Health Care. 2010;19(6):e59. 
– IHI/NPSF Lucian Leape Institute and NORC. Americans’ Experiences With Medical Errors and Views on Patient Safety. 2017. 
– Institute of Medicine. Crossing the Quality Chasm: A New Health System for the 21st Century. Washington, DC: National Academies Press; 2001. 
– Kausar S, Ambreen A, Andrades M. Role and influence of the patient’s companion. Journal of Family Medicine and Primary Care. 2013;2(3):283. 
– Khan S, Cholankeril R, Sloane J, et al. Current State of Diagnostic Safety. AHRQ Publication No. 24-0010-1-EF. January 2024. 
– Linzer M, Bitton A, Tu SP, et al. The end of the 15-20 minute primary care visit. Journal of General Internal Medicine. 2015;30(11):1584-1586. 
– National Academies of Sciences, Engineering, and Medicine. Improving Diagnosis in Health Care. Washington, DC: National Academies Press; 2015. 
– Newman-Toker DE, Nassery N, Schaffer AC, et al. Burden of serious harms from diagnostic error in the USA. BMJ Quality & Safety. 2024;33(2):109-120. 
– Shepperd JA, Waters EA, Weinstein ND, Klein WMP. A primer on unrealistic optimism. Current Directions in Psychological Science. 2015;24(3):232-237. 
– Silverman ME, Murray TJ, Bryan CS, eds. The Quotable Osler. Washington, DC: American College of Physicians; 2007. 
– Singh H, Giardina TD, Meyer AND, et al. Types and origins of diagnostic errors in primary care settings. JAMA Internal Medicine. 2013;173(6):418-425. 
– Singh Ospina N, Phillips KA, Rodriguez-Gutierrez R, et al. Eliciting the patient’s agenda. Journal of General Internal Medicine. 2019;34(1):36-40. 
– Smith KM, Baker K, Wesley D, et al. Guide to Improving Patient Safety in Primary Care Settings. AHRQ Publication No. 17-0021-2-EF. March 2017. 
– Weinstein ND. Unrealistic optimism about future life events. Journal of Personality and Social Psychology. 1980;39:806-820. 
– Weinstein ND. Unrealistic optimism about susceptibility to health problems. Journal of Behavioral Medicine. 1982;5:441-460. 
– Weinstein ND. Unrealistic optimism about susceptibility to health problems: conclusions from a community-wide sample. Journal of Behavioral Medicine. 1987;10(5):481-500.