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Study Highlights Need for Improvement of Patient Safety in Outpatient Settings

Research led by Boston area healthcare systems found that 7% of patients experienced at least one adverse event and 1.9% of patients experienced at least one preventable adverse event, calling attention to the need for evidence-based interventions

Key Takeaways

  • In a study of outpatient sites, researchers found that 7% of patients experienced at least one adverse event and 1.9% of patients experienced at least one preventable adverse event.
  • The most common adverse events in the outpatient setting were adverse drug events.
  • The findings highlight an urgent need to develop interventions to prevent both inpatient and outpatient harm.

Over the last several decades, research has brought nationwide awareness to issues of patient harm in the “inpatient” setting, where patients receive care as part of an overnight stay at a hospital. A new study reveals that patient safety events are also prevalent and persistent in the outpatient setting—primary care visits, specialty care appointments, day surgeries, visits to the emergency room and other settings where patients receive most of their care. To better understand patient safety in the outpatient setting, a team from Boston area hospitals used data from the SafeCare Study to analyze the care of patients seen in outpatient practices from four healthcare systems in Massachusetts in 2018. Led by investigators from Mass General Brigham and sponsored by CRICO, the medical professional liability insurer for the Harvard medical community and its affiliated organizations, the study provides insights into the most common forms of adverse events and populations most at risk, pointing to where interventions are needed most to improve patient safety. Results are published in The Annals of Internal Medicine.

“Our study is an alarm bell. About 1-in-4 people every month are touched by outpatient care, yet we do not know enough about its safety. If we do not measure outpatient safety, we cannot start to improve care for all patients,” said corresponding author David Levine, MD, MPH, MA, of the Division of General Internal Medicine and Primary Care at Brigham and Women’s Hospital, a founding member of Mass General Brigham. “Our study focuses on data that highlights what is a national and international issue for patients.”

Despite how frequently patients receive outpatient care, few studies have focused on this setting, and most of the studies that have done so to date have been limited and their findings have been imprecise.

“While there have been calls to look at safety issues related to inpatient care, we need to examine outpatient care, too,” said co-author Luke Sato, MD, of the Division of General Internal Medicine and Primary Care at the Brigham and SVP and CMO at CRICO. “Healthcare organizations everywhere need to take the first step of measuring patient safety in both inpatient and outpatient settings. This work is groundbreaking, but it’s also just the beginning.”

For the current study, researchers conducted a retrospective review of adverse events that occurred in the outpatient setting in 2018. They used all available data found in 3,103 electronic health records (EHR) for a random sample of patients aged 18 and over from 11 outpatient care facilities. Seven nurse reviewers identified possible adverse events by identifying relevant triggers noted in the EHRs. If a nurse found an adverse event in the EHR, they would hand the information to a physician adjudicator who determined whether it was indeed an adverse event. They then ranked the severity of the adverse event, assessed whether it was preventable and rated their confidence using a six-point scale.

They found 7% of patients experienced at least one adverse event in the outpatient setting and 1.9% of patients experienced at least one preventable adverse event. The most common adverse events were adverse drug events (63.8%), healthcare-associated infections (14.8%), surgical/procedural adverse events (14.2%), patient care adverse events (8.3%) and perinatal/maternal adverse events (0.7%). The team also found almost half of the adverse events occurred in the physician’s office, where patients more frequently receive care—for every 100 ED visits, approximately 2 adverse events occurred, while adverse events occurred in the physician’s office for about 1 out of every 100 ambulatory encounters.

The researchers also found that adverse events disproportionately affected older adults. Among patients over 85 years old, many had preventable (8.7%) and serious (4.4%) adverse events.

Investigators noted several limitations in the study. Since they analyzed and collected data retrospectively, some patient information may not have been captured in the EHRs. In addition, the team couldn’t access relevant data from patients who left the institutions from which the study data was collected. The investigators did not include the safety implications for telemedicine, which is an important aspect of practicing medicine today, but was infrequently practiced in 2018.

“Our results call for urgent measures to curtail outpatient harm,” said Levine. “They also have the potential to help inform evidence-based interventions, pointing us to where change could be most effective to help protect patients and prevent adverse events from occurring.”

Authorship: Mass General Brigham authors of the study include Ania Syrowatka, Hojjat Salmasian, David M. Shahian, Stuart Lipsitz, Jonathan P. Zebrowski, Merranda S. Logan, Christine Iannaccone, Michelle L. Frits, Lynn A. Volk, Sevan Dulgarian, Mary G. Amato, Heba H. Edrees, Luke Sato, Elizabeth Mort, David Bates. Additional authors include Laura C. Meyers, Christopher G. Roy, Patricia Folcarelli, Jonathan Einbinder and Mark E. Reynolds.

Disclosures: Disclosures can be viewed at

Funding: Supported by a grant from CRICO (A Reciprocal Risk Retention Group) and The Risk Management Foundation of the Harvard Medical Institutions Incorporated.

Paper cited: Levine, D et al “The Safety of Outpatient Health Care: The SafeCare Study” Annals of Internal Medicine DOI: 10.7326/M23-2063

For More Information: Findings from the SafeCare Study Underscore Importance of Patient Safety, Need for Continued Improvement 

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