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OTTAWA, May 4, 2001 - A new "rule" established by a team of Canadian physicians will help reduce the amount of over-ordered Computerized Tomography (CT) scans for minor head injuries, and ensure that serious head injuries do not go undetected. The Canadian CT Head Rule, a set of seven reliable decision criteria, could standardize the screening of minor head injuries around the world. The rules will be published in the May 5, 2001 edition of The Lancet, a prestigious medical journal. It is estimated that one million head injury patients come to North American emergency rooms on an annual basis. Most of these are considered minor, which by definition means they do not have clinically important brain injuries, nor do they require neurological intervention.

The standard tool for screening emergency head injuries is a CT scan. However, the use of CT is far from standardized, according to the principal investigator of the study, Dr. Ian Stiell, a Senior Scientist at The Ottawa Hospital Research Institute, and emergency room physician at The Ottawa Hospital. "What we noticed during this study is that the ordering of CT scans varied across the country." Researchers discovered that CT scans were ordered in varying rates due to a number of factors, including geographical area, the number of scanners per capita, accessibility to CT services, organizational culture, and lawsuit culture.

"The Canadian CT Head Rule was created to help standardize and improve patient care and make the process more efficient," says Dr. Stiell. "On one hand, we want to make sure physicians have the tools they need to help ensure that no serious head injuries slip through the cracks and are discharged before being detected. On the other hand, we don't think that requesting a CT for every minor head injury patient that walks through the emergency doors is a responsible or efficient way to operate either. The rule should help address the variation in current practice, and provide physicians with evidence-based guidelines to support their decisions." Dr. Stiell and his team of researchers also published clinical decision rules on radiological needs for ankle and knee injuries. The Ottawa Ankle Rules and Ottawa Knee Rules are being used in emergency rooms throughout the world, and becoming a part of standard training in many medical schools. Dr. Stiell is a Professor at the University of Ottawa, in the Division of Emergency Medicine, and the Department of Epidemiology and Community Medicine. This year, he became the fourth Canadian inductee into the Institute of Medicine (IOM) of the National Academy of Sciences, in its 30-year history. More recently, he was named a Distinguished Investigator for the Canadian Institutes for Health Research.

The Ottawa Hospital Research Institute was the lead for this study, that collected data from over 3,000 patients in ten medical centres across Canada. The study took three years to complete, and received generous support from the Canadian Institutes for Health Research and from Ontario's Ministry of Health and Long-Term Care.


For follow-up interviews with Dr. Stiell, contact:

Ron Vezina, Media Relations Officer, The Ottawa Hospital, (613) 737-8460

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