Until it happened to him, Itzhak Brook, a pediatric infectious disease specialist at Georgetown University School of Medicine, didn’t think much about the problem of misdiagnosis.
That was before doctors at a Maryland hospital repeatedly told Brook his throat pain was the result of acid reflux, not cancer. The correct diagnosis was made by an astute resident who found the tumor — the size of a peach pit — using a simple procedure that the experienced head and neck surgeons who regularly examined Brook never tried.
Because the cancer had grown undetected for seven months, Brook was forced to undergo surgery to remove his voice box. He believes that might not have been necessary had the cancer been found earlier.
“I consider myself lucky to be alive,” said Brook, now 72, of the 2006 ordeal, which he described at a recent international conference on diagnostic mistakes held in Baltimore. A physician for 40 years, Brook said he was “really shocked” by his misdiagnosis.
But patient safety experts say Brook’s experience is far from rare. Diagnoses that are missed, incorrect or delayed are believed to affect 10 to 20 percent of cases, far exceeding drug errors and surgery on the wrong patient or body part, both of which have received more attention.
Recent studies underscore the extent and potential impact of such errors. A 2009 report funded by the federal Agency for Healthcare Research and Quality found that 28 percent of 583 diagnostic mistakes reported anonymously by doctors were life-threatening or had resulted in death or permanent disability.
A meta-analysis published last year in the journal BMJ Quality & Safety found fatal diagnostic errors in U.S. intensive care units appear to equal the 40,500 deaths that result each year from breast cancer.
And a new study of 190 errors at a VA hospital system in Texas found many errors involved common diseases such as pneumonia and urinary tract infections; 87 percent had the potential for “considerable to severe harm” including “inevitable death.”
Misdiagnosis “happens all the time,” said David Newman-Toker, who studies diagnostic errors and helped organize the recent international conference. “This is an enormous problem, the hidden part of the iceberg of medical errors that dwarfs” other kinds of mistakes, said Newman-Toker, an associate professor of neurology and otolaryngology at the Johns Hopkins School of Medicine.
Studies repeatedly have found that diagnostic errors, which are more common in primary-care settings, typically result from flawed ways of thinking, sometimes coupled with negligence, and not because a disease is rare or exotic.
In the past few years, a confluence of factors has elevated the long-overlooked issue. In his 2007 bestseller, “How Doctors Think,” Boston hematologist-oncologist Jerome Groopman vividly deconstructed the flawed thought processes that underlie many diagnostic errors, including several he made during his long career.
More recently, an influential cadre of medical leaders has been pushing for greater attention to the problem. They cite concerns about the growing complexity of medicine and increasing fragmentation of the health-care system, as well as relentless time pressures squeezing doctors and the overuse of expensive, high-tech tests that have supplanted traditional hands-on skills of physical diagnosis.
“One of the reasons it’s time to begin looking at it is that so many of the quality measures we use now assume that the diagnosis is the right one in the first place,” said Christine Cassel; a member of the panel that wrote the 1999 IOM report, she is now president and chief executive officer of the American Board of Internal Medicine.
But what if it’s not?
In a much-cited essay, Robert Wachter, associate chair of the Department of Medicine at the University of California at San Francisco, wrote that a hospital could earn “performance incentives for giving all of its patients diagnosed with heart failure, pneumonia and heart attack the correct, evidence-based and prompt care — even if every one of the diagnoses was wrong.”
Unlike drug errors and wrong-site surgery — mistakes that patient safety experts consider to be “low-hanging fruit” amenable to solutions such as color-coded labels and preoperative timeouts by the surgical team — there is no easy or obvious fix for diagnostic errors. Many are complex and multifaceted, and may not be discovered for years if ever, said Graber, a senior fellow at RTI International, a research firm based in Research Triangle Park, N.C.
“There is probably nothing more cognitively complicated” than a diagnosis, he said, “and the fact that we get it right as often as we do is amazing.”
But doctors often don’t know when they’ve gotten it wrong. Some patients affected by misdiagnosis simply find a new doctor; unless the mistake results in a lawsuit, the original physician is unlikely to learn he blew it — particularly if the discovery is delayed. While diagnostic errors are a leading cause of malpractice litigation, the vast majority do not result in legal action.