“That’s a growing trend in insurance policies,’’ Ullmann said, “moving from a defined benefit to a defined contribution plan, much like with pensions. As a result, because now the person is going to be responsible for, say, the first $1,500 of costs, and then the insurance kicks in, the premiums for those insurance policies is going to be very low.’’

That’s also likely to spur consumers to shop around more since the first chunk comes out of their pockets, he said.

In South Florida and across the country, few if any hospitals publish prices for medical treatment. But some indicated they were intrigued by Sonenreich’s challenge.

Jackson Health System does not publish prices, said spokesman Ed O’Dell, but Miami-Dade’s safety net hospital for the poor and uninsured is open to the idea.

“Jackson sets the standard for transparency,’’ O’Dell said in a prepared statement. “We are always interested in new ways to share information, and we will explore this idea.’’

Memorial Healthcare System, which manages six hospitals in Broward, has published prices online and in marketing materials to promote imaging services, said Kerting Baldwin, a spokeswoman. But Memorial does not publish prices for diagnoses and treatments.

It was unclear from her written statement whether that might change: “Memorial Healthcare System has historically demonstrated transparency in the reporting of its finances, quality, safety and patient satisfaction data. Transparency in hospital pricing will be no different.’’

Baptist Health’s urgent care centers post prices for services, Keeley said, but the hospitals within the system do not.

Keeley said he worries that dumping raw prices on consumers would be more confusing than helpful because the prices Baptist Health charges private insurers are based on formulas different from the way the government reimburses hospitals.

“The problem with the pricing is it’s so convoluted,’’ he said. “It’s all pre-negotiated rates based many times on an aggregate number of per-stay, per-diagnosis or per-day, not broken down piecemeal.’’

The complexity of hospital prices may be one reason that information has not been divulged before.

When a patient asks a hospital the price for open heart surgery, the hospital might be able to give that person a ballpark range but not an exact amount because physicians don’t know how long that person will be in the operating room, or how many gauze pads they’ll need, or what equipment may be required.

Keeley said many hospitals have begun to “bundle” prices to include the charges that go into the total cost of treatment. Baptist Health’s urgent care centers already do this, he said.

Sonenreich has yet to say exactly what pricing information Mount. Sinai will reveal to the public, explaining that the hospital bills private insurers according to negotiated rates, sometimes at a per diem rate, sometimes as a percentage of cost.

He said he intends to meet with Mount Sinai’s executive team and decide what information to publish, most likely online and in a way that is “easily understandable for the public.”

Sonenreich said he’s not worried about losing a competitive edge by publishing Mount Sinai’s prices : “We’re already the lowest price.’’