Experts are fallible. Experts often disagree with each other. How, then, does one go about trusting experts? And how do we figure out which experts to trust, or not? Take, for instance, medical doctors…

The expertise of medical doctors lies in their ability to diagnose and treat injuries or illnesses. Unfortunately, doctors often get the first part wrong. For example, the authors of one study estimated that approximately 12 million adult outpatients are misdiagnosed in the US every year, with about half of these errors potentially harmful (Singh, Meyer & Thomas, 2014). Another study of patients referred for a second opinion found that in 88% of these cases, the final diagnosis was different than the referral diagnosis* (Van Such et al, 2017). And here’s a smattering of other research findings, all care of The incidence of diagnostic error in medicine (2013) by Mark Graber:

  • Autopsy studies identify major diagnostic discrepancies in 10–20% of cases.

  • Over half the surveyed pediatricians report making a diagnostic error at least once or twice a month.

  • Internists misdiagnosed 13% of patients presenting with common conditions to clinic.

  • Patients with asthma—median delay in making the correct diagnosis was 3 years, or 7 visits.

  • Delayed or wrong diagnosis rates of 10–50% have been identified in studies of coronary artery disease, HIV-associated complications, tuberculosis and a wide range of malignancies.

Graber concludes, “A wide variety of research studies suggest that breakdowns in the diagnostic process result in a staggering toll of harm and patient deaths.”

What about the treatment side of the equation?  Unfortunately, that’s too much for me to tackle in a post that’s already longer than intended. Obviously some medical conditions are relatively easy to diagnose and treat, others not so – for example, chronic back pain. Consider:

Between 1998 and 2008, the yearly number of lumbar fusion surgeries performed in the United States increased from 77,682 to 210,407, with the total number of spinal operations exceeding one million in 2002. The direct yearly cost of spinal fusion surgery in the United States was over US$ 16 billion in 2004, whereas the overall failure rate of lumbar spine surgery was estimated to be 10%–46%. Given that these rates have not changed substantially over the years despite advances in technology and surgical technique, the number of patients developing FBSS [Failed Back Surgery Syndrome] can be expected to continually increase. - Daniell & Osti (2018) Failed Back Surgery Syndrome: A Review Article

So if your doctor says you’d benefit from a spinal fusion, should you trust him? Assume the good doctor truly believes you’d benefit from surgery. But should you trust him and just go ahead with the surgery? Hell no - get a second opinion! And do some research yourself.

Trust is usually a matter of degree and threshold. The question is not: should I trust doctors? But: do I trust this doctor enough to follow her guidance? And at what point do I begin to question her guidance when it does not appear to be helping?

Note one can follow guidance faithfully without absolute trust in its source. At some point, however, something’s got to give. Trust has its limits.

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* Luckily, doctors often advise patients to seek a second opinion, especially when multiple body systems are involved and there is no definitive test to confirm the initial diagnosis.

References:

Daniell JR, Osti OL. Failed Back Surgery Syndrome: A Review Article. Asian Spine J. 2018;12(2):372-379. doi: 10.4184/asj.2018.12.2.372

Graber  ML.  The incidence of diagnostic error in medicine.  BMJ Qual Saf. 2013;22(suppl 2):ii21-ii27. doi:10.1136/bmjqs-2012-001615

Singh  H, Meyer  AN, Thomas  EJ.  The frequency of diagnostic errors in outpatient care: estimations from three large observational studies involving US adult populations.  BMJ Qual Saf. 2014;23(9):727-731. doi:10.1136/bmjqs-2013-002627

Van Such, M, Lohr, R, Beckman, T, Naessens, JM. Extent of diagnostic agreement among medical referrals. J Eval Clin Pract. 2017; 23: 870– 874. https://doi.org/10.1111/jep.12747

Why Second Opinions Matter: 88% Result in a Different Diagnosis. Jennifer Fink/Healthgrades Last updated: June 3, 2021.