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Colonoscopy top surgical procedure in Ontario, with regional variations in less common procedures


Colonoscopy is the most common procedure performed in Ontario, with relatively similar rates in all regions. However, less common procedures show more regional variation, according to a study by the Institute for Clinical Evaluative Sciences (ICES).

The study, published today in the journal CMAJ Open, was the first in nearly 20 years to systematically examine regional variation in surgical rates in Ontario.

“Twenty years ago when the last atlas of Ontario surgical rates was published, minimally invasive procedures were rare,” says senior author Dr. David Urbach, a staff surgeon at UHN and a lead scientist at ICES. “Since that time there have been large changes in practice, and so it’s important to take a look at current data to identify regional differences and find opportunities for province-wide improvements.” 

Researchers found that the most common procedure performed in Ontario was colonoscopy, followed by other endoscopic procedures including gastroscopy and cystoscopy, then cataract surgery, obstetric procedures (vaginal delivery, episiotomy, caesarian section), hernia repair, and knee replacement. These procedures were performed at relatively similar rates across Ontario counties.

Less common procedures showed more variation. The procedure with the largest regional variation was iridectomy, or surgical removal of part of the iris. Researchers found a nearly seven-fold difference between the lowest-rate to highest-rate counties. Another procedure with high regional variation was colposcopy, which may be indicated if a woman has an abnormal Pap smear. Cervical biopsies also demonstrated marked regional variation.

“The fact that we’re seeing regional variation in the use of surgery implies that there is uncertainty regarding appropriate use,” said Dr. Urbach. “By identifying which procedures have the most regional variation in Ontario, health providers can explore and address those differences to ensure that all patients in Ontario have access to the surgeries they need.”

Dr. Urbach cautions that these results do not necessarily mean that there are inappropriately high or low rates of use in certain regions. Rather, they could reflect different practice styles, patient populations, and health resources available.

The researchers used Canadian and provincial patient data to retrieve information on all surgical procedures conducted in Ontario between April 1, 2002 and March 31, 2011. They identified the 84 most common procedures and calculated rates for each in Ontario’s 49 counties. They chose to break down the regions by county rather than by LHIN to get a more precise regional picture.

“Regional variation in the use of surgery in Ontario” was published today in the journal CMAJ Open, a publication of the Canadian Medical Association.

Author block: Adina E. Feinberg, Joan Porter, Refik Saskin, Jagadish Rangrej and David R. Urbach

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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  • Kathleen Sandusky
  • Media Advisor, ICES
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