The Liberal government is reviewing all health services to see if evidence shows they improve patient outcomes, and if not, they could be delisted from OHIP, Matthews told reporters.
"We need to really be rigorous in our determination to fund services that have an evidence-basis and not fund those that don’t," she said.
The government found Ontario doctors perform far more C-sections than their colleagues in other jurisdictions.
"There’s pretty interesting research that demonstrates geographic differences in incidences of caesarean sections for example," said Matthews.
The ministry will rely on experts to decide if caesarean sections, or any other health services, should be delisted, added Matthews. Her office said later there were "no plans" to stop paying for all C-sections.
"That being said, the minister has been clear that if the procedure is medically necessary, OHIP will cover it," said press secretary Zita Astravas in an email.
Health care accounts for almost 44 per cent of government program spending, and Premier Dalton McGuinty said Tuesday the sector is "overflowing with opportunities for reform."
However, McGuinty declined to offer details Wednesday on how much the government thinks it can save in health care, and said Matthews would have more to say about the government's plans next week.
"I’ll be laying out several initiatives that will both improve patient care and will address the fiscal reality that we have," Matthews said as she too declined to talk about specifics.
The province saved $66 million by eliminating coverage for vitamin D testing, which evidence showed was not improving patient outcomes.
"So do we need to continue and indeed accelerate those evidence-based changes? Absolutely," said Matthews.
"But at the same time we need to fund things that do improve outcomes, so that’s why we brought in new childhood vaccines, for example."
The government "will have the courage to act on the evidence" as it decides which services to pay for and which to no longer cover, she added.
"Sometimes that will mean delisting. Sometimes that will mean doing things we aren’t already doing," said Matthews.
"So it cuts both ways."
The Opposition questioned what they see as McGuinty's new commitment to save money with his health-care reforms after the Liberals doubled provincial spending in the past eight years.
"Dalton McGuinty has to stop being the arsonist that sets the fires and puts himself on a fire truck so he can come and be the white knight that puts it out," said Progressive Conservative finance critic Peter Shurman.
"And that’s the situation we’ve got in Ontario now."
The New Democrats said the Liberals have a history of delisting health services and fear more substantial services will no longer be covered.
"Of course we're worried about this because it’s part of an agenda this government started eight years ago when they delisted chiropractors and physiotherapists and optometrists," said NDP finance critic Michael Prue.
"If it is confined to some narrow thing like tests that are no longer necessary fine, but she’s talking in much broader terms than that and that’s what causes me concerns."
One thing McGuinty said the government does want to look at is new medical technologies, which tend to be very expensive and often help doctors perform more efficiently, but never result in lower costs.
"In every other sector, when you invest in technology you reduce your costs and you pull those savings out of the system," said McGuinty.
"We have yet to effectively do that in health care here in Ontario."
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