The Society to Improve Diagnosis in Medicine has on its website this quote:

• 1 in 10 diagnoses are incorrect.
• Diagnostic error accounts for 40,000-80,000 U.S. deaths annually — somewhere between breast cancer and diabetes.
• Chances are, we will all experience diagnostic error in our lifetime.

The current focus on diagnostic error raises an interesting question:  Is this a larger problem in 2017 than in the 1970s and 1980s?

In this post, I postulate that the problem has increased.  Several factors likely contribute to the problem.  Of course, I may just be an old guy pining for the “good old days” (that actually were not that great), but I will leave that postulate to your interpretation.

The diagnostic process requires that the physician first value diagnosis and respect its complexity.  The best diagnosticians are skeptical questioners.  They never assume a diagnosis, but rather challenge every diagnosis, at least internally and often externally.

Unfortunately, our health care payment process has implicitly undervalued the diagnostic process.  The current guideline process often over simplifies diagnosis or assumes the diagnostic process occurs prior to needing the guideline.

A few examples might put these thoughts into context.  Sore throat guidelines have oversimplified acute sore throat diagnosis into group A strep versus unimportant viral infection.  Yet sore throats are much more complex and even potentially dangerous.  Having guidelines state that the patient either has group A strep or nothing important sends a message to physicians that halts the diagnostic process.

Patients presenting with dyspnea and wheezing and a smoking history get diagnosed with COPD, even when they have had no pulmonary function studies done.  Patients with dyspnea and peripheral edema get treated for systolic dysfunction even though no test has measured their systolic function.  Physicians accept an imaging diagnosis of cirrhosis in the absence of any clinical signs or laboratory abnormalities.

Several factors play into diagnostic naïveté.  The first is the incredibly simplistic rule that patients must have a diagnosis prior to hospital admission.  This rule comes from insurers.  Thus the emergency department has to “make a diagnosis,” even when they have inadequate information.  The problem here is that once a patient has a diagnostic label, some physicians use that diagnosis as an anchor that is heavily weighted.  They have difficulty escaping that diagnostic trap.

The next problem comes from how insurers now grade physicians.  We get no scores related to diagnostic accuracy; rather we get scores related to performance (prescribing the proper medications or achieving goal levels of tests).  Thus, many physicians assume that performance measures have greater importance, and thus spend less energy on the diagnostic process.

Some physicians ignore the noise and focus on getting the proper and correct diagnosis.  These physicians have the same mindset as many detectives in novels, TV, and movies.  They do not accept diagnoses made on insufficient data.  They question all diagnoses and look for diagnostic errors.  They more often feel uncomfortable with given diagnoses and then become diagnostic bulldogs.

Diagnosticians implicitly understand test characteristics.  They know the limitations of radiologic testing and laboratory testing.

Recently on twitter, @medicalaxioms tweeted:

With a dimer, a BNP, a lactate and a troponin, I can get nearly any patient into a bed in the hospital.

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The problem here is that too often the admitting physician does not understand the context of the test.  They do not understand sensitivity and specificity.

We recently had a patient admitted for a sub-segmental pulmonary embolus.  The patient had no risk factors and no symptoms.  I never really understood why they got the CTA.  The next morning the attending physician re-read the images and called us to tell us that the patient did not have an embolus.

This raises several interesting questions.  Do you treat a sub-segmental pulmonary embolism in a patient with risk factors or significant clinical suspicion?  Do you even order a CTA?

Often patients get admitted for community acquired pneumonia (CAP).  Some actually do have CAP, but too often the patient’s story and physical exam do not match the story and exam of a CAP patient.  Too many CXRs seem over-read.  By the time we see the patient they already have received antibiotics.  Our job is to rethink the problem.  Perhaps they patient has CAP, but we must never accept that diagnosis until we re-examine the evidence.

For that should be our mission.  We should protect our patients from incorrect diagnoses.  Patients deserve diagnostic excellence.

Diagnostic excellence requires an attitude.  It requires extra time; time that too often one must donate.  It requires that we understand how to take careful histories, do appropriate examinations and understand how to interpret test results.

We must once again make the term diagnostician the most prestigious term in medicine.  We should celebrate the great diagnosticians for they truly help patients.

Patients understand this.  How do we get the insurers and wonks to focus more light on this problem?

Robert Centor is an internal medicine physician who blogs at DB’s Medical Rants.

Image credit: Shutterstock.com