During Sunday's U.S. presidential debate, Republican candidate Donald Trump said Canada's "catastrophic" health-care system is prompting Canadians to head south for treatment — but a new report says the number of health tourists has fallen year over year.

The Fraser Institute report estimates that about one per cent of Canadian patients who received treatment from a specialist in 2015 got that treatment outside of Canada.

The report estimates that percentage translates into 45,619 Canadians, slightly lower when compared with the 52,513 who went abroad for medical treatments in 2014, but higher than the 41,838 in 2013.

The report does not break down the numbers to determine how many Canadians went to the U.S. for treatment, but just refers to those who have received treatment in another country.

The report focuses on 12 types of specialist treatments such as urology, neurosurgery and plastic surgery, but does not explain why Canadians chose to travel abroad — just that they did.

But one of the report's authors, Bacchus Barua, a senior economist with the Fraser Institute, said there are a number of likely reasons some Canadians travel abroad for treatment. Chief among them is wait times, something Trump referred to in the debate.

"If you've ever noticed the Canadians when they need a big operation when something happens they come into the United States in many cases," Trump said on Sunday. "Because their system is so slow, it's catastrophic in certain ways."

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According to the Canadian Institute for Health Information, 70 per cent of Canadian doctors said they thought their patients often experienced long wait times to see a specialist, the highest out of the 10 countries compared in the study.

The number is well below the average in comparative countries, but has improved from 75 per cent in 2009.

The average of Canada, New Zealand, Germany, Australia, Sweden, Norway, the U.K., the U.S., the Netherlands and Switzerland was 45 per cent, with Switzerland being the lowest at nine per cent.

Once Canadians patients have seen a specialist, the timeliness of care improves, with only 21 per cent of Canadian doctors saying they thought their patients often had to wait a long time to get treatment. The number was 29 per cent in 2009.

The 2015 Commonwealth Fund Survey notes that the average of the 10 countries was 19 per cent, with New Zealand having the most patients waiting at 33 per cent and Switzerland the least at just one per cent.

Canada's wait time story, however, varies greatly by region. Between 2014 and 2015 the number of patients who sought treatment abroad rose in Newfoundland and Labrador, B.C., New Brunswick and Nova Scotia, while they went down in Saskatchewan, Manitoba, Alberta, Ontario and Quebec.

*Residual count was produced using the average provincial per cent of patients receiving treatment outside of Canada and the residual count of procedures produced in Waiting Your Turn, 2015 report (Waiting Your Turn 2015, calculations by authors) ( Source: Fraser Institute/Kevin Kirk/CBC)

The report says that aside from wait times, people may travel abroad because a given procedure is not available in Canada, while others may have chosen to go abroad simply because they can afford to get treated immediately.

"It's not something that we know," said Barua. "It's not one reason, but likely a variety of reasons why Canadians might be doing it."

Barua said that while the report does not offer prescriptions for how to improve Canadian health care, countries with better wait times usually do three things differently than Canada:

Include some private partnership or private sector alternatives to government-funded health care.

Implement a cost-sharing user fee model where patients pay a deductible or flat fee for accessing services.

Fund hospitals based on the number and type of patients they treat rather than providing a global budget.

By the numbers

The authors of the report note that the numbers are not definitive, but rather estimates calculated by combining responses from about 2,000 specialist doctors and information from the Canadian Institute for Health Information on how many procedures were performed in Canada, in a given specialist area, each year.

"The number of patients receiving treatment outside Canada each year produced by this methodology is likely to be an underestimate," the report says, noting that patients who leave Canada for treatment without consulting a specialist would not be counted.

The report also notes that the estimates were calculated based on the number of procedures performed, which is lower than the number of patients that consulted specialists.