Study: Minor ailments don't cause ED overcrowding

Culprit: Delays for sicker patients

Patients who come to EDs with minor conditions do not contribute significantly to delays and overcrowding, despite widely held beliefs to the contrary, according to a new study published on-line by the Annals of Emergency Medicine.1

"Our research shows that caring for patients with minor ailments [or low-complexity patients] does not lead to longer delays or slower care for other, sicker patients," said Michael Schull, MD, an emergency physician at the Institute for Clinical Evaluation Services in Toronto, and the article's lead author, in a prepared statement from the American College of Emergency Physicians. "We already know that it is delays in the care of sicker patients, especially those who require hospital admission, that lead to worsened crowding. Therefore, our study suggests that low-complexity patients are not a key contributor to overcrowding."

10 minor ailments equal 5.4 minutes

Over a one-year period (April 2002 to March 2003), Schull and his team studied 4.1 million patient visits at 110 emergency departments in Ontario hospitals. 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.

The study suggests that reducing the number of low-complexity patients in EDs would do little to reduce ED delays for sicker patients and, hence, do little to reduce crowding. One likely explanation is that most patients with minor ailments or injuries are not usually placed in the treatment spaces used for sicker patients. In addition, the resources they require are generally simple and readily available, and staff allocates time to these patients in lower priority than they do for sicker patients.

However, Thomas Granchi, MD, medical director of Ben Taub General Hospital Emergency Center in Texas' Harris County, told the Houston Chronicle that Schull's findings are "counterintuitive" and do not affect physicians' "assumptions or current knowledge."2 He added that the study compares "apples and oranges," as the United States and Canadian health systems differ.


  1. Schull MJ, Kiss A, Szalai JP. The effect of low-complexity patients on emergency department waiting times. Ann Emerg Med Aug. 25, 2006. DOI: 10.1016/j.annemergmed.2006.06.027.
  2. Ackerman T. "Study casts doubt on policy to help ERs." Houston Chronicle, Aug. 23, 2006, Section B, p. 1.