WASHINGTON — Imagine walking into a hospital and being charged more than $10,000 for a blood test to check your cholesterol level. And going to another hospital in the same state and being charged $10 for the same test. That was what a team led by a University of California San Francisco researcher found when it looked at prices California hospitals charge for 10 common blood tests.

Researchers studied charges for a variety of tests at 160 to 180 California hospitals in 2011 and found a huge variation in prices. The average charge for a basic metabolic panel, which measures sodium, potassium, and glucose levels, among other indicators, was $214. But hospitals charged from $35 to $7,303, depending on the facility. None of the hospitals was identified.

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The biggest range involved charges for a lipid panel, a test that measures cholesterol and triglycerides, a type of fat in the blood. The average charge was $220, but costs ranged from a minimum of $10 to a maximum of $10,169. Yes, more than $10,000 for a test that doctors typically order for older adults to check their cholesterol levels.

The smallest range was for a blood test that checks an individual’s red and white blood cells. It cost $37 to $278.

The study was published Friday in the British Medical Journal Open.

Senior researcher Renee Hsia, associate professor of emergency medicine at UCSF and director of health policy studies at the Department of Emergency Medicine, studies disparities in health costs. But even Hsia, who is also an emergency physician at San Francisco General Hospital, was taken aback at the differences.

‘‘I was very surprised.’’

Unlike other medical services or procedures that might vary by patient or doctor, these blood tests are common, simple, and standard procedures.

In general, county hospitals and teaching hospitals had lower prices than non-teaching hospitals, not-for-profit, and for-profit hospitals, she said.

The study’s main conclusion is that there is no clear explanation for the price differences, Hsia said.