In May, an Edmonds, Wash., woman was arrested for using another woman's identity to obtain nearly $180,000 worth of medical services and prescription drugs.

It's a form of identity theft that doesn't happen as often as cases involving stolen credit cards or forged checks, but medical identity theft can be equally time-consuming and frustrating to resolve.

Authorities say Barbara Reuter took her victim's personal information —- including date of birth, Social Security number and other information —- and convinced doctors that she was a real Medicaid client. She was caught when the health plan's billing department noticed duplicate billings for virtually simultaneous medical visits.

How can you protect yourself against medical identity theft?

Closely monitor your "explanation of benefits," the statement your health insurer sends out to tell you what health services you have obtained and how much they plan to reimburse you. Monitor your credit reports, and guard your medical information.

Three percent of U.S. identity theft victims, or about 249,000 people, were victims of medical identity theft in 2005, according to the Federal Trade Commission.

Medical identity theft can take many forms.

A thief may use your information to obtain medical treatment, services or goods in your name.

Or a person may steal your medical records and sell the information to organized crime rings, which then submit false health claims and bills in your name.

You may not realize you've been a victim until you get a bill for a procedure you didn't receive. Or you may even be denied insurance coverage for a medical history that's not yours.

"A medical record has a tremendous amount of information," said Peter Winn, an assistant U.S. attorney who teaches privacy law at the University of Washington. "It has your Social Security number, which is probably the keys to the kingdom, a tremendous amount of personal information and family medical history."

There's not a lot of choice in handing over detailed information, since doctors and hospitals need it to treat you and to get paid for it, Winn said. "You're not in a position to say you don't want to give them a Medicare number."

There are some ways that consumers can protect medical identity, said Alex Johnson, a former special agent with the FBI who now heads the investigative unit for Regence BlueShield.

"The key is to be cognizant of the fact that someone can use your medical ID," Johnson said.

Read your explanation of benefits carefully when you get it from your health insurer. Did you have an X-ray as it states? Did you actually visit Dr. Smith?

Shred any discarded medical information as you would a credit card or bank statement. And never give your health insurance number over the telephone or Internet.

Under federal law, you have the right to request copies of your current medical records from your doctor. Johnson suggests periodically reviewing your files to ensure they are accurate. Correct any inaccurate or missing information.

You also have a right to get an accounting or "histories of disclosure" of everyone who has been given access to your medical records by your insurer or doctor. This may help you track down where inaccurate information has been sent.