It sounds like something out of a horror movie, but wrong-sided surgery happens more often than you think.

Concerns about surgeons operating on the wrong part of the body made headlines this week after The Providence Journal reported that on three separate occasions this year, surgeons at Rhode Island Hospital operated on the wrong side of a patient’s head. The most recent case happened last Friday, when the chief resident started to cut on the head of an 82-year-old patient. The resident, a doctor in the seventh year of specialty training, realized the error before reaching the skull and closed the wound with a single stitch. The procedure was done on the correct side, “with good results,” according to a statement from the hospital, which was fined $50,000 by the state health department.

On a percentage basis, surgery on the wrong side or area of the body is considered rare. But nonetheless, it affects hundreds of people a year, and hundreds more cases likely go unreported. This month, the Archives of Surgery ran a letter from The Joint Commission, the primary accrediting agency for hospitals in the United States, noting that it receives about nine voluntary reports per month of so-called “wrong-site adverse events” to its Sentinel Event Database. Last September, the same medical journal reported that wrong-site surgery may be underreported by a factor of 20. That study concluded that there are 1,300 to 2,700 wrong-site procedures annually in the United States.

Many mistakes involve near misses, like the recent case in Rhode Island, where the surgeon starts to cut but realizes the mistake before real damage is done. Sometimes the mistake has dire consequences. In one widely publicized Florida case a few years ago, a series of mistakes by medical staff resulted in a doctor amputating the wrong leg. British doctors in 2002 were tried and acquitted for manslaughter when a patient died after they removed the wrong kidney.

In July, another surgeon at Rhode Island Hospital drilled into the wrong side of an 86-year-old patient’s head during an emergency procedure. The doctor realized his mistake and operated in the correct place. However, the patient died a few days later, but a preliminary investigation showed the patient didn’t die as a result of the surgical error, reports The Providence Journal.

The Joint Commission has a set of guidelines for hospitals to follow to prevent wrong-site surgery. They require hospitals to verify the surgical procedure to be performed, mark the surgical site in advance and take a “time out” immediately prior to starting the operation, during which team members verify that they’ve got the right patient, ensure that scan films aren’t reversed and confirm that medical records and scans match the marked surgical site.

Patients who have scheduled surgical procedures can adopt some simple strategies to protect themselves from wrong-site surgery.

Speak directly with the surgeon just prior to your surgery to discuss the specifics of the operation he or she is scheduled to perform. Talk to the surgeon before you are prepped or given any anesthesia.

Don’t let nurses or other surgical staff mark the surgical site. Insist that the surgeon who will be doing the cutting use a permanent marker to mark the incision site. In Canada, surgeons are advised to put their initials on the place to be cut. “It’s very reasonable to ask and participate in the marking of the site,” said Dr. Peter Angood, vice president and chief patient safety officer of the Joint Commission.

As you interact with surgical nurses, anesthesiologists, radiologists and other providers prior to the surgery, confirm they know what procedure you are scheduled for.

Talk to your doctor about what procedures the hospital has in place to prevent medical mistakes like wrong-site surgery, and make sure the hospital where your operation is being performed is accredited by The Joint Commission.

“I think a patient should recognize that they have the ability to prevent this,” said Dr. Angood. “Each time they talk to the surgeon or people involved in the procedure they should verify that it’s the right leg or the left arm. As they move into the procedure area, the patient and patient’s family shouldn’t hesitate to ask, and re-ask, the nurses and the providers, ‘Are you sure we’re doing the correct side?’ ”

The commission lists these tips for patients to help prevent wrong-site surgery. The page also includes a brochure for download called “Help Avoid Mistakes In Your Surgery” that includes a checklist of extra precautions for surgical patients.