Here's a scary statistic: Medical bills are responsible for half--yes, half--of all bankruptcies, according to a recent Harvard University study.

Researchers found that in the event of a medical emergency, someone with insurance will still spend an average of $13,000 for out-of-pocket costs like co-payments, deductibles and uncovered services.

A financial intervention now could save you bundles later. Here, three ways to get started saving:

1 Question your statements. Nine out of 10 medical bills contain errors, according to the Medical Billing Advocates of America, a consumer-advocacy group based in Salem, Va., and one study found that more than 75 percent of post-service health insurance coverage appeals are won. Always ask for an itemized bill so you can be on the lookout for overcharges, duplicate bills for the same service or charges for services you never received.

To back up your claim, make sure you've saved everything--co-pay receipts, pre-certification letter and explanations of benefits, says Martha Priddy Patterson, a director of Human Capital Services at Deloitte Consulting in Washington, D.C. To protect your credit rating, remind the billing department in writing that you're disputing this bill.