During Sunday night’s American presidential debate, Donald Trump called Canada’s health care system "slow" and "catastrophic," and that "when [Canadians] need a big operation […] they come into the United States."

And while Canada may not be fond of being dragged into the debate, Trump’s words aren’t entirely baseless.

A new study by Fraser Research Institute shows that an estimated 45,619 Canadians received non-emergency medical treatment outside of Canada in 2015.

It’s a drop from 2014 where they reported an estimated 52,513 Canadians chose to go abroad -- but still higher than 2013 when 41,838 travelled abroad.

The study surveyed physicians across Canada in 12 major medical specialties and found that overall, one per cent of patients leave the country for medical treatment.

Similar to last year, they also found that British Columbia had the highest proportion of patients travelling abroad to receive treatment (1.6 per cent), while Ontario had the largest number of medical tourists at 22,352.

The most common procedures sought abroad were urological procedures; with urologists reporting the highest proportion of patients travelling abroad for treatment (1.6 per cent).

“A large number of Canadians clearly feel they have to leave the country to obtain needed and timely medical care,” said Bacchus Barua, study co-author at the Fraser Institute, in a statement.

He told CTVNews.ca that he wouldn’t be surprised if wait times were a key factor in why some Canadians are crossing borders.

The report outlines that in 2015, wait times were over 9 weeks between seeing a specialist and receiving treatment, which is almost 3 weeks longer than doctors consider being ‘reasonable’.

According to Barua, it’s an issue that doesn’t have many solutions.

“We need to look at ways to help deliver on the universal health care promise,” he said.

But Dr Valorie Crooks, Canada Research Chair in Health Service Geographies, told CTVNews.ca: “They can’t hang their hat exclusively on wait times,” explaining that people travel for a variety of reasons.

Crooks listed motives such as: procedures being unavailable, immigrants wanting to receive their care in their native country, anonymity and ‘snowbirds’ being treated for chronic conditions while away.

“Even the act of being placed on a waitlist is enough to prompt some people to consider seeking treatment elsewhere,” she added.

“The fact of the matter is [medical tourism] is a practice that is untracked, untraced and unregulated. There are speculative accounts but all numbers are unreliable.”

In other words, there’s really no way of knowing how many Canadians are actually going abroad for medical treatment or why.

And while Trump puts Canadians’ health care system in his crosshairs, Canada is ranked as the number one medical tourist destination, receiving over 16.6 million tourists per year, according to the medical tourism index.