Adverse Events in Hospitals May be Ten Times Greater Than Previously Measured

April 7, 2011

Adverse event detection methods commonly used to track patient safety fared very poorly compared to other methods and missed 90% of events.

A study released today has concluded that the adverse event detection methods commonly used to track patient safety in the United States fared very poorly compared to other methods and missed 90% of adverse events.

“Overall, adverse events occurred in one-third of hospital admissions,” the authors wrote in the abstract of their article, which was published in the April issue of Health Affairs. “Reliance on voluntary reporting and the patient safety indicators could produce misleading conclusions about the current safety of care in the US health care system and misdirect efforts to improve patient safety.”

The issue also includes case studies illustrating some successes that hospitals have had in improving quality of care and patient safety. “As a number of articles in the issue demonstrate, there’s no doubt we’ve made progress—but it’s also clear that making any headway has been agonizingly slow. If ever the state of high-quality health care appeared to be an achievable end point, we recognize now that—to paraphrase Ralph Waldo Emerson—quality, like life, is not a destination but a journey,” journal editor Susan Dentzer, wrote in an accompanying editorial, “Still Crossing the Quality Chasm—or Suspended Over it?”

David C. Classen, MD, of the University of Utah, and colleagues reviewed medical records for 795 patients at three large US hospitals that had “well-established operational patient safety programs.”

They searched patient paperwork for “triggers,” notations indicating problems, such as a stop order on medication or an abnormal lab result. The team further investigated the triggers to see whether there had been an adverse event, and how severe it might have been.

Classen and his colleagues used the Institute for Healthcare Improvement’s Global Trigger Tool, which involves reviews of patient charts by nurses, pharmacists, and physicians.

They detected 354 adverse events among the patients, 10 times more than other methods in use. Overall, adverse events occurred in 33.2% of admissions.

“Our study suggests that despite sizable investments and aggressive promotional efforts by local hospitals, these reporting systems fail to detect most adverse events,” the researchers wrote.

“To be sure, not all of these resulted in serious injuries to patients or deaths,” Dentzer wrote in her editorial. “But try to imagine the reaction if one of three patients arriving at hospitals were notified that something bad would happen during their stay—and that, to make matters worse, they might be stuck with higher hospital copayments as a result.”