Johns Hopkins University Study: Misdiagnosis the Most Harmful Medical Mistake
Which of the following medical errors is the most costly and harmful?
- Surgical mistakes
- Medication errors
If you chose #3, then you have a pretty good handle on the medical malpractice situation in the United States. However, even if you got it right (which is not the average response), you probably have no idea how right you were. That’s the conclusion of an eye opening study by Johns Hopkins University School of Medicine, published in the online edition of the journal BMJ Quality and Safety.
The Johns Hopkins researchers reviewed 25 years (1986-2010) of malpractice claim payouts in the United States. They found that diagnostic errors had the highest total of penalty payouts. In fact, payments related to misdiagnosis totaled $38.8 billion over the period – and this did not include diagnostic errors that did not lead to insurance payouts.
It’s not hard to understand that mistakes made right at the beginning of the medical process – where it’s decided what’s wrong with you – might be a fundamental problem.
For the purpose of analysis, diagnostic errors come in three flavors: Missed diagnosis (where the correct diagnosis is overlooked), wrong diagnosis, or delayed diagnosis (where the correct diagnosis was made too late to do any good). There are many possible combinations for misdiagnosis, for example, harm caused by treating the wrong illness or failure to treat an illness when the working diagnosis was unknown. Not all diagnostic errors are serious and relatively few wind up in malpractice suits, but the study estimated that the number of patients suffering from potentially preventable, significant injury or death from misdiagnosis is about 80,000-160,000 per year in the U.S.
This is a rather shocking figure and it is considerably more than any other medical treatment related error. Out of 350,706 claims analyzed by the study, 28.6% were diagnostic errors, accounting for 35.2% of all payouts. Diagnostic errors resulted in death or disability more than twice as often as any other category.
Diagnostic errors are a particularly difficult problem for medicine. For one thing, as any honest physician will tell you, medical science doesn’t have enough knowledge to correctly diagnose every illness. If you’ve ever watched an episode of House, you know the drill. Diagnosis can be an art as well as science and given all the variations in people and the diseases they present, there are bound to be cases that simply can’t be fully diagnosed. Other times, it’s necessary to start with one diagnosis, perform a treatment and see what happens before going on to another diagnosis. And that’s when money or expertise is no object.
In the real world (not TV medical shows), diagnostic errors, whether well intentioned or just routine, occur with regularity. By one estimate, up to 15% of new case diagnoses are in error. According to David Newman-Toker, leader of the Johns Hopkins study, “Overall, diagnostic errors have been underappreciated and under-recognized because they’re difficult to measure and keep track of owing to the frequent gap between the time the error occurs and when it’s detected.” This is in comparison to improper medication or surgical mistakes, which tend to have immediate and highly noticeable effects.
The study noted that diagnostic errors tended to cause more cases of serious neurological harm, such as quadriplegia or brain damage, resulting in lifelong care. The payment for this care was even higher than malpractice claims for death. The researchers believe the incidence of permanent severe harm is underreported because the figures are based on autopsy reports only from errors resulting in death.
From the cost to the medical system point of view, diagnostic errors are pernicious and often subtle. In addition to malpractice payouts (which are not subtle), there are costs associated with sequential treatments based on partially missed or delayed diagnosis, and even more subtle – the cost of unnecessary testing. In an effort to “do all they can” to avoid malpractice suits for misdiagnosis, doctors often attempt to bolster their positions with a wide array of tests, at great expense.
With today’s diagnostic tools, especially the scanning equipment such as MRI and CAT-scan, and the emphasis on “defensive medicine,” the cost of diagnosis is already very high and climbing relative to other aspects of medical treatment. However, despite the improvement in tools, the rate of misdiagnosis does not seem to be declining.
The Johns Hopkins study takes the position that while diagnostic mistakes will not be solved with a silver bullet; the time has come for the research community and the medical profession to seriously examine the procedures, ethics and outcomes of diagnosis. New techniques, such as computer assistance, new diagnostic tests and above all new protocols for checking diagnoses should be tried and analyzed. As the study highlights, diagnostic errors are the biggest problem in medical treatment; there just hasn’t been enough attention paid to it.