In the Philadelphia region, the price of a colonoscopy appears to be all over the map, ranging anywhere from $800 to $8,000.

That's based on self-reported information from about a dozen people who entered what they were charged and what they paid for a colonoscopy into WHYY's searchable PriceCheck database.

 As Dr. Neel Shah, an associate professor at Harvard recently told The Pulse, one reason prices for medical procedures may vary is because, well, they can.

"You know it's just the market at work. It's the same reason why different restaurants can charge different prices for a hamburger," said Shah. "The difference with a hamburger is you kind of know the quality you're getting as soon as you bite into it. With a colonoscopy, it's much harder to know the quality."

At closer look, these self-reported colonoscopy prices around Philadelphia may be hard to directly compare because colonoscopy prices are complicated. They may vary depending on what's involved in the procedure and how it's billed. Shah also cautions people to beware of potential hidden expenses.

That's in part because, under the Affordable Care Act, insurance fully covers a colonoscopy if it's preventive. That could change, midprocedure.

"You do a screening of a colonoscopy because you're looking for polyps and other things that might be suspicious," said Shah. "The trick is, if you find something that is suspicious and needs a biopsy, that biopsy might be billed separately."

A case study

At the urging of his doctor, Ed Rhoads went in for a preventive colonoscopy at a nearby center, Hillmont GI Associates in Flourtown, Pennsylvania.

Rhoads received several different charges, including one for anesthesia, one for the removal of a polyp, and another for the consequent pathology examination. The total charge: $3,710.

Rhoads has Medicare, which lowered that combined price for all the colonoscopy-related procedures to $1,079.

"I actually paid nothing," said Rhoads, adding that his supplemental insurance covered what Medicare didn't of that $1,079 charge.

But why the huge difference between the charge and what insurance paid? This perplexed Rhoads.

Experts say it's because that charge, $3710 in this case, is just a starting point. Insurers and providers individually negotiate or contract actual prices. The agreements tend to be confidential.

Richard Gundling, with the Health Care Financial Management Association, said because Medicare is a government payer, it sets the rate in most cases with no negotiation, and those rates tend to be lower. It "pays providers in a given area fairly uniformly," he said, with some differences due to geography and teaching costs.

But what if Rhoads didn't have Medicare or any insurance at all? Or what if he had a plan with high out-of-pocket costs?

Dr. Gerald Bertiger is one of the doctors at Hillmont GI, where Rhoads went for his procedure. Ignore Rhoads' initial $3,710 charge, he said.

"We get that from nobody. Zero," he said.

Bertiger said the whole billing process -- and trying to figure out how to get reimbursed for what he does -- is really complicated, even for him. He has five full-time employees whose sole job is to work on billing issues.

That $3,710 charge is meaningless, said Bertiger, adding that back in the '70s and '80s, insurance companies used to pay a percentage of that list price, so providers had an interest in making it higher.

"So if my list price was higher than the same practice next door, I got more money for the same procedure," he said. "But that hasn't gone on for 25 years."

These days, anyone coming in to Bertiger's practice without insurance would pay Medicare rates, not that higher list price.

"We feel it's unfair for an insurance company to get a break from the list price, yet the person who's going to shell out the money has to pay the list price," he explained.

Provider reported self pay colonoscopy prices around Philadelphia range from $900 - $2100

A WHYY survey with ClearHealthCosts.com of about 15 other providers found that self-pay prices that included the lab, facility and anesthesia fees ranged anywhere from $900 to $2,100. Others that just included the facility fees ranged from $769 to $2,000.

Keep in mind, this is tricky. A given price may not account for if a doctor finds a growth and has to remove it. It may or may not represent the total cost, depending on whether the doctor or facility fees are included in that price.

Shah said it might be difficult to get an exact price in advance, but asking the right questions, such as 'is that the total cost?', can help prevent major sticker shock down the road.

What did you pay for a colonoscopy or other procedure? Contribute to WHYY's PriceCheck project here: www.whyy.org/pricecheck.