Skip Navigation
Search Menu

Medical Rounds

The ‘Big 3’ in Diagnostic Errors

For a patient, a diagnostic error can mean the difference between life and death. It’s estimated that more than 100,000 Americans die or are permanently disabled each year due to medical diagnoses that initially miss conditions or are wrong or delayed.

Now a Johns Hopkins research team reports it has identified three major disease categories — vascular events, infections and cancers — that account for nearly 75 percent of all serious harms from diagnostic errors. The team’s findings, based on analysis of a large repository of malpractice insurance claims, were published recently in Diagnosis.

“We know that diagnostic errors happen across all areas of medicine. There are over 10,000 diseases, each of which can manifest with a variety of symptoms, so it can be daunting to think about how to even begin tackling diagnostic problems,” says team leader David Newman-Toker, director of the Johns Hopkins Armstrong Institute Center for Diagnostic Excellence. “Our findings suggest that the most serious harms can be attributed to a surprisingly small number of conditions. It still won’t be an easy or quick fix, but that gives us both a place to start and real hope that the problem is fixable.”

The researchers found that diagnostic errors were the most common, most catastrophic and most costly of medical mistakes. Diagnostic errors leading to death or serious, permanent disability were associated with misdiagnosed cancers (37.8 percent), vascular events (22.8 percent) and infections (13.5 percent) — categories that the team calls the “big three.”

The authors describe 15 big three conditions that together account for nearly half of all the serious, misdiagnosis-related harms. The top conditions in each category are stroke, sepsis and lung cancer, respectively. These are accompanied by heart attack, venous thromboembolism, aortic aneurysm and dissection, arterial thromboembolism, meningitis and encephalitis, spinal infection, pneumonia, endocarditis, and breast, colorectal, prostate and skin cancers.

Based on claims data, the analysis also found that failures of clinical judgment were identified as causes in more than 85 percent of the misdiagnosed cases. The researchers say this adds to growing evidence that health care systems must do more to support bedside diagnostic decision-making by clinical providers. The authors point to interventions such as deploying computer-based diagnostic decision support tools, increasing immediate access to specialists at the point of care, supporting more effective teamwork and patient engagement in diagnosis, providing routine diagnostic performance feedback for clinicians, and improving diagnostic education through simulation training.