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ICES study shows that ED waiting times and crowding not affected by patients with minor ailments


Patients who visit emergency departments (EDs) with minor illnesses and injuries do not have a substantial effect on the overall waiting times of other ED patients or ED crowding, a new study from the Institute for Clinical Evaluative Sciences (ICES) shows.

“We have confirmed one conclusion from the recent Ontario expert panel report on ED crowding: less serious patients coming to the ED for care are not an important cause of ED crowding,” said Dr. Michael Schull, ICES scientist.

In their report, Dr. Schull and his fellow investigators tracked 4.1 million ED visits to 110 Ontario hospitals between April 2002 and March 2003. They analyzed the how the number of new low-complexity ED patients (defined as those who were triaged as less-urgent or non-urgent, did not arrive at the ED by ambulance, and were discharged home) that arrived seeking care impacted the average ED length-of-stay and time to first-physician-contact for other ED patients.

They found that every 10 patients with minor ailments arriving in any eight-hour period added only 5.4 minutes on average to the length-of-stay and 2.1 minutes on average to the time spent waiting to see the doctor, for patients with more serious medical problems. These results were similar regardless of the ED volume or whether the institution was a teaching hospital or not.

“These delays are not clinically important and have a negligible effect on the overall waiting time of other emergency department patients,” said Dr. Schull.

“While low-complexity patients represent half of all patients seen in community and teaching hospital EDs in Ontario, they do not have a substantial impact on the efficiency or timeliness of care given to other, more acutely ill, ED patients.”

The authors conclude that reducing the number of low-complexity patients in EDs would do little to improve ED performance for sicker patients, and hence would do little to reduce crowding. “Low-complexity patients do not use the same treatment spaces as sicker patients, the resources they require are generally simple and readily available, and there is either staff dedicated to their care, or they are triaged as lower priority than sicker patients,” said Dr. Schull.

“Therefore, in order to address the complex issue of ED crowding, some initiatives hospitals could focus on include increasing the number of inpatient beds and moving patients efficiently through tests such as X-rays. These initiatives should help to ensure that sicker patients who require these resources are not waiting for them and causing a back-up in the ED.”

The study, “The effect of low-complexity patients on emergency department waiting times”, is published online in the Annals of Emergency Medicine.

Author affiliations: ICES (all authors); Clinical Epidemiology Unit, Sunnybrook Health Sciences Centre (all authors); Department of Emergency Services, Sunnybrook Health Sciences Centre (Dr. Schull); Department of Medicine, University of Toronto (Dr. Schull).

ICES is an independent, non-profit organization that uses population-based health information to produce knowledge on a broad range of healthcare issues. Our unbiased evidence provides measures of health system performance, a clearer understanding of the shifting healthcare needs of Ontarians, and a stimulus for discussion of practical solutions to optimize scarce resources. ICES knowledge is highly regarded in Canada and abroad, and is widely used by government, hospitals, planners, and practitioners to make decisions about care delivery and to develop policy.


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