Global Trigger Tool

Error catching tool discovers 1 in 3 patients are harmed

This tool identified 354 instances of harm where physicians, nurses and other health professionals reported only four "events," and that is in spite of the fact that the global trigger tool doesn’t catch iatrogenic injuries that should have been treated but weren't, and it doesn't catch misdiagnoses - the most common cause of patient harm, and it doesn't account for all that is off-screen as a result of evidence of harm so rarely being put in the record, this last of which is probably the most common event of all.

Most of what follows was written by Kevin B. O'Reilly of the amednews staff with notes and editing by Joel Selmeier.

One-third of hospital patients experience adverse events and about 7% are harmed permanently or die as a result, according to a study that detected patient safety problems at a far higher rate than other methods.

Two reports in Health Affairs in November 2010 showed rates of adverse events hovering near 25% among hospitalized Medicare patients nationwide and at 10 North Carolina hospitals. This report carries that work further.

The findings draw attention to the safety troubles that have lingered in U.S. hospitals in the years since the Institute of Medicine's headline-grabbing report "To Err is Human." That study cited research estimating that up to 98,000 patients die each year due to preventable medical errors. Since then larger studies have found the number more likely to be 400,000 unnecessary patient deaths per year (see Preventable Deaths).

"This is one of the best studies that now gives us a sense of how much harm is happening to patients in American hospitals," said Robert Wachter, MD, chief of the medical service at the University of California, San Francisco Medical Center, who was not involved in the research. "There is a tremendous amount of harm befalling patients who are admitted to hospitals and humongous opportunities for improvement."

There have been improvements in patient safety, but it is uneven, according to Mark R. Chassin, MD, president of the Joint Commission, which accredits hospitals and other health care organizations.

"What we have been doing for the last 10 or 15 years has produced some important progress, but it has not produced the kind of improvement that anybody wants to see," he said. "The progress is not broad enough across the different services that are delivered in health care, and it's not consistent within health care, whether at physician practices, hospitals or facilities of any sort. And it's not deep enough."

Dr. Chassin, who co-wrote a separate article in the April Health Affairs, said physicians and hospitals should look to "high-reliability industries" such as commercial aviation to develop processes that identify systemic weaknesses before they result in harm. But do you think that physicians and hospitals ever will recognize their own conflict of interest as a systemic weakness? Pilots in aviation do not have that conflict of interest. Doctors and nurses do. But we have never seen a patient safety initiative that took it into account (see Conflict of Interest). Until they do, physicians and hospitals will continue to be the last people who make the kind of safety improvements that Mark R. Chassin wants to see.

Error-catching tool

The April 2011 issue of Health Affairs contains a study that uses a technique developed at the Cambridge, Massachusettes-based Institute for Healthcare Improvement. The method, called the Global Trigger Tool, is a chart review process, as was the method used in the landmark Harvard Medical Practice Study cited in "To Err is Human," but ramped up.

Nurses and pharmacists trained to review charts systematically look for notes revealing "triggers," such as medication stop orders and abnormal laboratory results, that can be indications of an adverse event. The trigger prompts further investigation to determine whether the event caused harm and, if so, how severe it was. IHI makes the tool available at no cost to hospitals and researchers.

"The Trigger Tool is a more modern, more refined, more efficient version" of the Harvard Medical Practice Study, said David C. Classen, MD, lead author of the study and associate professor of medicine at the University of Utah School of Medicine in Salt Lake City.

Dr. Classen and his colleagues found that in the 795 patient records they reviewed from three large tertiary care centers, the Global Trigger Tool detected 10 times as many adverse events as the Agency for Healthcare Research and Quality's Patient Safety Indicators, which use billing data to spot events such as decubitus ulcers and postoperative sepsis. And where the Trigger Tool identified 354 total instances of harm, physicians, nurses and other health professionals reported only four adverse events using their hospitals' voluntary reporting systems. Note, where the researchers found "harm" the caregivers reported "events" (and only about 1% of those).

The tool "is far and away the most sensitive and the most reliable measure we have in patient safety," said Christopher P. Landrigan, MD, lead author of a study in the Nov. 25, 2010, New England Journal of Medicine that used the method to examine adverse events at 10 North Carolina hospitals.

Avoidable errors

The vast majority of the adverse events identified in the Health Affairs study -- 93% -- required medical intervention but did not permanently injure or kill the patient. Most were medication-related or nosocomial infections. The study did not attempt to estimate how many of the adverse events could have been prevented.

The NEJM study said 63% of the adverse events that reviewers identified could have been avoided. A November 2010 report from the Dept. of Health and Human Services' Office of Inspector General that used the Trigger Tool for Medicare patients estimated that 44% were preventable.

On April 12, HHS Secretary Kathleen Sebelius announced the "Partnership for Patients" initiative aimed at preventing 60,000 health care-related deaths and avoiding $50 billion in Medicare costs over 10 years.

The program will disburse $1 billion under the Patient Protection and Affordable Care Act to reduce hospital readmissions and cut hospital-acquired conditions such as pressure ulcers and catheter-related urinary tract infections.

Also in April, the Centers for Medicare & Medicaid Services, over objections from the American Hospital Assn., began reporting individual hospital performance on hospital-acquired conditions at its Hospital Compare website.


Detecting adverse events

Hospital efforts to improve patient safety are impeded by a failure to systematically track when patients are harmed. A review of 795 patient records at three tertiary care centers found that the Global Trigger Tool uncovers far more adverse events than other methods.

Severity of adverse event IHI Global
Trigger Tool
AHRQ Patient
Safety Indicators
Hospital voluntary
reporting system
Temporary harm, required intervention 204 23 0
Temporary harm, required prolonged hospitalization 124 7 2
Permanent patient harm 8 1 2
Required life-saving intervention 14 0 0
Patient death 4 4 0
Total 354 35 4

Source: " 'Global Trigger Tool' Shows That Adverse Events In Hospitals May Be Ten Times Greater Than Previously Measured," Health Affairs, April (