Researchers at a hospital in England have found that even when patients speak the same language as their doctors, they may not understand them.

Jayshree Dave and I. Hill-Smith of the Luton and Dunstable Hospital in Bedfordshire, England, asked 100 patients whose mother tongue was English to give the meanings of 15 common terms they were likely to hear from their doctors.The 93 patients who agreed to take the written quiz did best in defining "diabetes," "diet," "drip," "tumor," and "drug," with more than 70 patients giving the correct definitions, the scientists said in a recent issue of the British medical journal The Lancet.

Less than half the patients knew the meaning of "biopsy," "steroid," "myocardial infarction," or "heart failure." Heart failure is any condition in which the heart cannot pump enough blood to the body's organs. Sixty-eight of the patients answered incorrectly.

The same number of patients gave no answer for "myocardial infarction," which is a medical term for heart attack or a blockage of a heart artery caused by hardening of the arteries or a blood clot.

"Words commonly used by doctors are often misunderstood by patients, and most will approach someone other than a doctor to explain them," the researchers said. "Doctors should explain in plain English the meaning of medical words."