After reviewing 25 years’ worth of payouts for malpractice claims in the U.S., researchers determined that diagnostic errors represented the largest proportion of claims, the most serious patient harm and the highest total of penalty payouts.
As reported by ScienceDaily.com, the researchers from Johns Hopkins Hospital found that diagnostic errors accounted for 28.6% of the 350,706 paid claims they analyzed, and 35.2% of total payments. These mistakes resulted in death or disability nearly twice as often as other error categories, including surgical mistakes and medication errors.
“This is more evidence that diagnostic errors could easily be the biggest patient safety and medical malpractice problem in the United States,” lead author David E. Newman-Toker, M.D., Ph.D., told ScienceDaily. “There’s a lot more harm associated with diagnostic errors than we imagined.”
By error category, death (as opposed to serious harm) percentages of malpractice claims were:
- diagnosis: 40.9%
- medication: 38.7%
- treatment: 25.7%
- obstetrics: 22.7%
- surgery 13.8%.
The study examined only claims that resulted in a malpractice payout-most incidents of malpractice never see the light of litigation. Researchers estimate the number of patients suffering misdiagnosis-related, possibly preventable, significant permanent injury or death in the U.S. each year could be 80,000 to 160,000 people. Many routine diagnostic errors result in costly patient inconvenience and suffering; one estimate suggests an average diagnostic error rate of 15 in 100 when patients consult doctors for a new problem.
The study was published in BMJ Quality and Safety in Health Care. According to MedPageToday.com, the authors analyzed data from the National Practitioner Data Bank (NPDB), an electronic record of payments made on behalf of physicians with medical liability settlements or judgments. It also tracks adverse peer review actions against licenses, clinical privileges and professional society memberships.
A diagnostic error can involve a diagnosis that is missed, wrong or delayed. Harm can result from the delay or failure to treat a problem because the initial diagnosis was wrong or unknown, or from a treatment given to address a condition the patient didn’t have.
By category of diagnostic error, percentages of malpractice payouts were:
- missed diagnosis: 54.2%
- delayed diagnosis: 19.9%
- misdiagnosis: 9.9%.
Much of the remaining percentage was unclassified.
The study authors said diagnostic errors are tricky to track and quantify because often there’s a big gap between when the error occurs and when it’s detected. It’s easier to recognize other malpractice mistakes, such as operating on the wrong body part or giving someone the wrong dose of medicine-those harms present quickly.
Treatment errors were responsible for 27.2% of the study’s total, and surgery-related errors amounted to 24.2%.
As Newman-Toker said, the difficulty of identifying a diagnostic error is compounded by human errors of commission: Experts often minimize the scope of diagnostic errors not because they were unaware of them, but “because they were afraid to open up a can of worms they couldn’t close.”
By more than double, diagnostic error claims were the result of outpatient rather than inpatient care, but inpatient errors were more likely to be lethal.
Between 1986 and 2010, diagnosis-related payments totaled $38.8 billion, and per-claim payments were highest for mistakes causing serious neurologic harm, such as quadriplegia and brain damage requiring lifelong care. Such payments were more than for errors resulting in death.
It’s difficult to pin down the complete cost of diagnostic errors. Newman-Toker told Science Daily that tens of billions are spent every year on “defensive medicine,” which, as readers of this blog know, is when doctors order tests that might be unnecessary solely to protect themselves from being accused of neglecting to do something. “Yet diagnoses are still missed, with grave consequences,” Newman-Toker said.
Which confirms the wealth of evidence that “defensive medicine” does nothing to immunize someone from making errors, large or small.
The public health effect of diagnostic errors, the authors said, probably is much greater than previously believed because earlier estimates were based on autopsy data. That information counts only deaths, not disability.
“Despite their significant impact, diagnostic errors have received relatively limited public and scientific attention, even from the patient safety community,” the authors wrote.
As noted by MedPageToday, the diagnostic error scenario could be even bleaker than this study suggests: Practitioner data in the NPDB is incomplete, and it might grossly underestimate diagnostic errors because many lawsuits are dismissed before settlement.
“We found roughly equal numbers of lethal and nonlethal errors in our analysis, suggesting that the public health burden of diagnostic errors could be twice that previously estimated,” the authors said. “Healthcare stakeholders should consider diagnostic safety a critical health policy issue.”