And it's behavior like this that could help shake up the way the health-care industry does business.
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"It surprised us in health care that millennials would be so opinionated and vocal on this," said Ceci Connolly, director of PwC's Health Research Institute. "For the most part, they're still young and relatively healthy, so we didn't think that they would engage much on this topic."
But the findings come as no surprise to millennial Jen Mishory, executive director of Young Invincibles, a lobbying group that focuses on policy issues impacting young people.
"You're looking at a generation that has significant student debt, that has wages that have declined more rapidly than for older workers," she explained.
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Mishory points to a Commonwealth Fund study that showed just over 1 in 3 young adults struggled to pay health bills or medical debt before the expansion of Obamacare coverage in 2012. An updated version of that survey found the number had not changed last year.
"Young people are trying to make sure they are getting the best deal possible because they need the best deal possible," Mishory said.
Having grown up being able to compare prices for everything from air fares to electronics, millennials expect the same transparency in health care. While just 10 percent of the general population will inquire about costs for a treatment, 17 percent of 18 to 24 years olds surveyed by PwC said they ask about pricing, and 21 percent of those ages 25 to 34 said they ask for a price check on medical care.
"I think it's going to be great for the health-care system to have people actually really making sure that they're getting the best deal possible and really demanding transparency," said Mishory.