10 Conditions Doctors Often Miss

Colorectal cancer, lung cancer and breast cancer are the three most frequently missed diagnoses in outpatient clinics and academic medical centers, a January 2022 study published in JAMA Network Open found. Heart attack and prostate cancer round out the top five.

Combing through data from patient safety incident reports, malpractice claims, morbidity and mortality rounds (conferences that review patient deaths and complications), and focus group responses, researchers found 836 relevant diagnostic errors, which they used to identify the 10 most common missed or delayed diagnoses and explore what went wrong in the process. The findings highlight what experts say is a key safety issue in modern medical care.

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“Missed diagnoses are common, and they’re often overlooked,” says study coauthor Gordon Schiff, M.D., associate director of Brigham and Women’s Center for Patient Safety Research and Practice and an associate professor of medicine at Harvard Medical School in Boston.

In fact, research shows that some 12 million American adults are misdiagnosed annually in outpatient settings. That’s about 5 percent of patients, though some experts say the percentage is likely higher. And a new study published in the medical journal BMJ estimates that roughly 795,000 Americans become disabled or die each year because of a misdiagnosis.

Why do diagnostic errors occur?

Reasons for diagnostic errors run the gamut. Sometimes it’s miscommunication between patient and doctor: The patient may fail to describe their symptoms accurately, or the doctor misses something important in the patient’s story. Other times an incorrect test is ordered, or a test is read incorrectly. Data in electronic medical records can be disorganized, and sometimes referrals aren’t followed up on.

“It could be so many of those reasons,” even multiple reasons, says Hardeep Singh, M.D., a professor of medicine at Baylor College of Medicine and chief of Health Policy, Quality and Informatics (HPQI) at the Michael E. DeBakey VA Medical Center in Houston.

“You also can’t overlook the fact that “there’s a lot of uncertainty in diagnosis,” Schiff says. There are several thousand known diseases but only so many symptoms.

“When you go to your primary care doctor complaining of a headache, there’s a long list of possibilities [of what might be causing it],” says David Newman-Toker, M.D., a professor of neurology, ophthalmology and otolaryngology and director of the Armstrong Institute Center for Diagnostic Excellence at Johns Hopkins University School of Medicine. The same can be said for stomach pain or back pain.