Experts estimate that 90% of hospital bills contain errors. And those mistakes can add up to big, unexpected costs for patients. For example, if a doctor’s office or hospital enters an incorrect procedure code, it may not be covered by your insurance. Other billing errors include things like adding an extra zero to a price – so an $80 medication becomes $800.

So how can you protect yourself? Try these tips:

•Ask for an itemized copy of your bill. A lot of patients find unfair or excessive charges for items like gowns, toothbrushes, or gauze, that are supposed to be included as part of room and board or operating room charges.

•Look for typos, like an extra zero added to the price of an item. And make sure you weren’t charged for tests you didn’t have.

•You should also watch out for double-billing. For example, you might get billed for a scalpel…When you’ve already been billed for an “operating kit” that includes a scalpel.

If you see any unusual charges on your bill, make an appointment with the medical provider to go over it. And if you need help, try a service like Medical Billing Advocates of America – at BillAdvocates.com. This company charges a portion of the money they help you recoup.