Medical Errors Ten Times More Frequent Than Reported

Medical errors and other adverse events occur in one-third of hospital admissions, which is as much as 10 times more than some previous estimates have indicated, according a new study.

“Without doubt, we’ve seen improvements in health care over the past decade, and even pockets of excellence, but overall progress has been agonizingly slow,” said Susan Dentzer, editor in chief of the peer-review health policy journal, Health Affairs, where the study is reported this month.

“It’s clear that we still have a great deal of work to do in order to achieve a health care system that is consistently high-quality — that is, safe, effective, patient-centered, efficient, timely, and devoid of disparities based on race or ethnicity.”

According to the researchers, voluntary hospital reporting of errors and federal reporting guidelines do not give an accurate picture of patient safety in the United States.

The patient safety study, conducted by David C. Classen of the University of Utah and coauthors at the Institute for Healthcare Improvement, compared three methods for detecting adverse events in hospitalized patients, including the Institute’s own Global Trigger Tool. The study drew on comparable samples of patients from three leading hospitals that had undertaken quality and safety improvement efforts.

Among the 795 patient records reviewed, voluntary reporting detected four events, the Agency for Healthcare Research and Quality (AHRQ) Indicators detected 35, and the Global Trigger Tool detected 354 events, which is 10 times more than the AHRQ method.

In other words, the AHRQ indicators and voluntary reporting missed more than 90 percent of adverse events identified by the Global Trigger Tool. If anything, the researchers say, their findings are conservative, because they rely on medical record review, which would not detect as many adverse events as direct, real-time observation would.

The researchers say that reliance on voluntary hospital reporting or the AHRQ indicators could lead to seriously flawed perceptions of patient safety in the United States. They also note that the Global Trigger Tool detected a much higher rate of adverse events for hospitalized patients than previous studies have shown. Although the Global Trigger Tool is a somewhat more resource-intensive method because it involves medical record review, the researchers suggest that it could be incorporated into commercial electronic health record systems, thus making it easier and less costly to use.

Health Affairs, published by Project HOPE, is a monthly peer-reviewed journal.

Other recent Health Affairs papers that examine the current state of US health care quality include:

• An analysis by Jill Van Den Bos and colleagues at Milliman’s Denver Health practice in Colorado, based on insurance claims, estimated the annual cost of measurable preventable medical errors that harm patients to be $17.1 billion in 2008 dollars. Ten types of errors accounted for more than two-thirds of the total cost, with the most common ones being pressure ulcers, postoperative infections, and persistent back pain following back surgery. The researchers recommend that these three types of errors receive top priority for intervention and improvement.

• John C. Goodman of the National Center for Policy Analysis, and coauthors, found that there is a social cost to adverse events, and it is based on what people would be willing to pay to avoid the risk of death or injury caused by medical management. That dollar figure ranges from $393 billion to $958 billion. Yet the United States has few policies to compensate patients harmed by medical errors, other than a “very imperfect tort system,” in which fewer than 2 percent of patients harmed ever file a malpractice suit and even fewer receive any compensation, the researchers note.

• Widespread and serious racial and ethnic disparities in health care have previously been well-documented. Amal N. Trivedi of the Providence Veterans Affairs (VA) Medical Center and Brown University, along with several colleagues, studied the VA’s efforts to combat disparities. They found that although care “process” outcomes–such as rates of eye exams for people with diabetes–improved, disparities in health outcomes–such as control of blood pressure, glucose, and cholesterol– persisted. The difference between the clinical outcomes of black veterans as those of white veterans was as much as nine percentage points. The authors call for more focused achieve racial equity for more complex measures of chronic disease management.