"It used to be it was just poor people" who lacked health insurance, said Deborah D. Oswalt, executive director of the Virginia Health Care Foundation. But today, "so many people who are uninsured have a decent education and a full-time job, and a chunk of them have fairly decent incomes."

For people like these -- and for those who have insurance but still need to keep their co-payment and deductible expenses down -- shopping for even such common procedures as an X-ray or an MRI scan can be difficult.

"It's a very complex system," said Robin Norman, chief financial officer for Virginia Hospital Center (VHC) in Arlington. A prospective patient can get an estimate of the likely charge for a procedure, she said, but that range of prices is not precise.

Michael Lundberg, executive director of Virginia Health Information, a nonprofit that offers consumer guides and other data on health care providers (www.vhi.org), said if he were seeking a good price for a non-urgent procedure, he would seek bids from several hospitals. "If I went to buy a car, I would do the same thing."

American Hospital Directory (AHD) offers free information on its Web site (www.ahd.com) that may steer you in the right direction. The firm recently posted financial data on outpatient procedures that had been performed on Medicare patients. (While District and Virginia hospitals are included in this report, Maryland institutions are not.)

For example, AHD reports that Medicare -- as one would expect of the federal insurance plan for seniors -- paid almost identical sums ($413 to $423) to five local hospitals for a particular type of MRI scan. But the official "charges" for those procedures ranged from a low of $1,984 (at VHC) to more than $2,400. In one category of X-ray, the charges ranged from $116 to $162. VHC had the highest price for a gastrointestinal procedure -- $1,319, compared with as little as $692 elsewhere.

Why such variation? In a category as broad as outpatient GI care, each patient requires somewhat different care, said Norman, who added that Medicare patients "tend to have more things wrong with them" than the general patient population.

For more than 90 percent of VHC's patients, Norman said, "it doesn't matter what the charges are," either because a lower rate has been negotiated with their insurer or because they are written off as charity cases. "What we're paid has very little to do with what we charge."

But Paul Shoemaker, chairman of AHD, said private insurers generally pay one-third to one-half of a hospital's official charges. As a result, said Oswalt, AHD's list "could be a good tool for people" who need to balance their financial health with their physical health.

-- Tom Graham

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