Misdiagnosis Seriously Harms 795,000 People Annually: Study

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July 19, 2023 – An estimated 795,000 people in the U.S. die or are permanently disabled each year due to misdiagnoses. Stroke topped the list of misdiagnosed medical problems that result in serious harm.

About 3 in 4 of all misdiagnoses happen to people experiencing one of the so-called “Big Three” – heart events like a heart attack, infections, or cancer. Specifically, in addition to stroke, the most common ailments that result in death or disability due to misdiagnosis are sepsis, pneumonia, blood clots in veins, and lung cancer.

On average, the researchers estimated that 11% of medical problems result in a misdiagnosis, although the error rate varies widely depending on the disease. The misdiagnosis rate for heart attack is just 1.5%, but it’s 62% for spinal abscesses.

Measuring harm caused in the course of practicing medicine has been a difficult research area due to challenges in compiling accurate data. Published Monday in the journal BMJ Quality & Safety, this latest study created estimates by heavily relying on known error rates that occur with specific diseases.

The research was a collaboration by teams from the Johns Hopkins Armstrong Institute Center for Diagnostic Excellence and the Risk Management Foundation of the Harvard Medical Institutions. 

“Reducing diagnostic errors by 50% for stroke, sepsis, pneumonia, pulmonary embolism and lung cancer could cut permanent disabilities and deaths by 150,000 per year,” said researcher David Newman-Toker, MD, PhD, director of the Center for Diagnostic Excellence, in a statement.

The estimates were created by multiplying how many people in the U.S. have a disease by the number of people known to experience harm or errors. The researchers tallied the estimates for 15 diseases and applied those patterns to all dangerous diseases, according to a research summary from Johns Hopkins Medicine. Each year, an estimated 371,000 deaths occur from misdiagnoses, in addition to 424,000 permanent disabilities.

“Diagnostic errors are, by a wide margin, the most under resourced public health crisis we face, yet research funding only recently reached the $20 million per year mark,” Newman-Toker said. “If we are to achieve diagnostic excellence and the goal of zero preventable harm from diagnostic error, we must continue to invest in efforts to achieve success.”