ONE consequence of the high cost of medical care in the United States has been the rise of medical tourism. Every year, thousands of Americans undergo surgery in other countries because the allure of good care at half the price is too good to pass up.

Average total fees at well-regarded hospitals like Apollo and Wockhardt in India are 60 percent to 90 percent lower than those of the average American hospital, according to a 2007 study by the consulting group Mercer Health and Benefits (where Dr. Milstein is affiliated). Even compared with low-cost American hospitals, the offshore fees are 20 percent to 50 percent lower.

Most medical travelers seek cosmetic procedures like facelifts and liposuction, but an increasing number have high-risk operations like heart surgery and joint replacement in places like India, Singapore and Thailand.

Is this a good idea? The only way to know is to find out how foreign hospitals and surgeons compare with their American counterparts.

Which Americans consider this option? Typically, they are people who have either no health insurance or meager coverage. Though not poor enough to qualify for Medicaid, they cannot afford a good health plan. But lately, even some people with good coverage have been encouraged to take advantage of cost savings abroad.