Publisher Health

As many as 250,000 people die every year because they are misdiagnosed in the emergency room, with doctors failing to identify serious medical conditions like stroke, sepsis and pneumonia, according to a new analysis from the federal government.

The study, released Thursday by the Agency for Healthcare Research and Quality, estimates roughly 7.4 million people are inaccurately diagnosed of the 130 million annual visits to hospital emergency departments in the United States. Some 370,000 patients may suffer serious harm as a result.

Researchers from Johns Hopkins University, under a contract with the agency, analyzed data from two decades’ worth of studies to quantify the rate of diagnostic errors in the emergency room and identify serious conditions where doctors are most likely to make a mistake. Many of the studies were based on incidents in European countries and Canada, leading some officials of U.S. medical organizations to criticize the researchers’ conclusions.

While these errors remain relatively rare, they are most likely to occur when someone presents with symptoms that are not typical, like stroke patients complaining the room is spinning.

A doctor may not immediately think that a young woman with shortness of breath is having a heart attack or that someone who has back pain could have a spinal abscess.

“This is the elephant in the room no one is paying attention to,” said Dr. David E. Newman-Toker, a neurologist at Johns Hopkins University and director of its Armstrong Institute Center for Diagnostic Excellence, and one of the study’s authors.

The findings underscore the need to look harder at where errors are being made and the medical training, technology and support that could help doctors avoid them, Dr. Newman-Toker said. “It’s not about laying the blame on the feet of emergency room physicians,” he said.

In reviewing the studies, the researchers also found that women and people of color had a roughly 20 to 30 percent higher risk of being misdiagnosed. While these results are not surprising, they point to the need to address how different patients are assessed in the emergency room as part of the effort to improve care, said Jennie Ward-Robinson, the chief executive of the Society to Improve Diagnosis in Medicine. “Equity must be core and must be fundamental,” she said.

Medical societies representing emergency room doctors strongly criticized the study. “In addition to making misleading, incomplete and erroneous conclusions from the literature reviewed, the report conveys a tone that inaccurately characterizes and unnecessarily disparages the practice of emergency medicine in the United States,” Dr. Christopher S. Kang, the president of the American College of Emergency Physicians, said in a statement.

“As with all medical specialties, there is room for improvement in the diagnostic accuracy of emergency care,” Dr. Kang added. “All of us who practice emergency medicine are committed to improving care and reducing diagnostic error.”

Doctors say addressing diagnostic errors is challenging. While the National Academy of Medicine identified medical errors as a critical issue more than 20 years ago, most of the efforts to improve patient safety have focused on mistakes that are easier to identify, like when a patient gets the wrong medicine or develops an infection while in the hospital, said Dr. Robert Wachter, the chairman of medicine at the University of California, San Francisco, who had not seen the full report. “Diagnostic errors are a huge part of the problem,” he said.

The deaths that the report suggests occur every year “is a very concerning number,” Dr. Wachter said. The study’s findings are higher than previous estimates, he noted.

The researchers largely relied on studies conducted outside the United States, in countries like Canada, Spain and Switzerland, to come with up with their overall estimate of error and harm rates. But Dr. Kang argued the reliance on these studies may have distorted the findings and led the researchers to overestimate the number of mistakes. “While most medical specialties have similar training in Western nations, emergency medicine does not,” he said.

The study’s authors acknowledged the need to do more research looking specifically at emergency rooms in the United States. “We need studies done in the United States,” said Dr. Susan M. Peterson, a Johns Hopkins emergency medicine physician who is also one of the study’s authors. “It’s a huge gap in the literature.”

But she also emphasized the benefit of paying more attention when doctors tend to miss a crucial diagnosis. In recent years, she said, doctors have become much better at detecting heart attacks because of a concerted effort involving public health campaigns, better diagnostic testing, and collaboration between cardiologists and emergency medicine doctors to address the issue.

Experts also emphasized that while the study focused on those mistakes made in emergency rooms, where a harried doctor, dealing with overcrowding, must make a quick decision about what is wrong with a patient, the issue of misdiagnosis is a common problem among all doctors.

“The bottom line is diagnosis is hard,” said Dr. Doug Salvador, an infectious disease specialist who is the board president of the Society to Improve Diagnosis in Medicine and the chief quality officer at Baystate Health in Springfield, Mass.

The researchers found that teaching hospitals were less prone to errors. Emergency room doctors working at an academic medical center may be able to consult with a specialist who is familiar with patients who have atypical symptoms, and they may have more resources to offer a wider range of tests or to keep patients longer while they figure out what’s wrong.

The study also suggested that doctors were more likely to miss specific diseases. A patient with a spinal abscess, for example, is more frequently misdiagnosed than someone having a heart attack.

Some doctors warn that the answer is not simply to do more testing. “This is a really complicated calibration problem,” Dr. Wachter said. “The answer can’t be let’s test everybody for all this stuff all the time,” he said.

The Johns Hopkins researchers say there needs to be more effort to understand how to avoid the most deadly errors, including thinking about how doctors are trained and what kinds of technology could help alert them to a possible missed diagnosis. “This is going to have to be a sustained effort, and that requires resources and support,” Dr. Newman-Toker said.

Not enough money is being spent on how to improve diagnosis despite its role in improving care, Dr. Peterson said. “A lot of research dollars are focused on treatment,” she said. “That’s a little more sexy than diagnosis.”