‎What do hospitals charge to remove an appendix? The startling answer is that it could be the same as the price of a refrigerator - or a house.

A California study found huge disparities in patients' bills - $1,500 to $180,000, with an average of $33,000. The researchers and other experts say the results aren't unique to California and illustrate a broken system.

"There's no method to the madness," said lead author Dr. Renee Hsia, an emergency room physician and researcher at the University of California, San Francisco. "There's no system at all to determine what is a rational price for this condition or this procedure."

The disparities are partly explained by differences among patients and where they were treated. For example, some had more costly procedures, including multiple imaging scans, or longer hospital stays. A very small number were treated without surgery, though most had appendectomies. Some were sicker and needed more intensive care.

But the researchers could find no explanation for about one-third of the cost differences. The study was published Monday in the journal Archives of Internal Medicine.

--ASSOCIATED PRESS