2005-6-21
This is Gwen Outen with the VOA Special English Health Report.
"Placebo" is a Latin word. It means "I shall please." And, sometimes, it just might.
When scientists want to test a new drug, they usually divide a large number of people into two groups. One group takes the medicine. The other takes a substance known as a placebo. It may contain nothing more than sugar.
The people do not know which pill they are taking -- the active one or the inactive one. In this kind of experiment, the medicine must perform better than the placebo to prove it is effective.
Yet people who take a placebo sometimes experience improvements in their health. This is known as the "placebo effect," the effect of something that is not supposed to have any effect.
Some doctors even use the placebo effect in their treatments. They might tell patients that a new drug will stop their pain. The patient does not know that the pills are inactive. The patient takes the pills and later tells the doctor that the pain is gone.
Now, research in Sweden suggests that placebo treatments can also reduce the emotional effects of unpleasant experiences. The effects in the brain were similar to those seen when placebos have been used to ease pain. The researchers say that in both cases, expectations of improvement are a major influence on the effectiveness of placebos.
The new study involved a group of people who looked at unpleasant pictures, such as images of dead bodies. Predrag Petrovic of the Karolinska Institute in Stockholm led the study. The findings appeared in the publication Neuron.
An influential study on placebos appeared in nineteen fifty-five. It said treatment with a placebo made patients feel better thirty-five percent of the time. But in two thousand-one, Danish researchers reported that they had examined more than one hundred studies. They found little evidence of healing as a result of placebos.
Some researchers think a good relationship between a doctor and patient can increase the effectiveness of real medicines.
In any case, some medical researchers are against the use of placebos. They think it is wrong to give some people inactive substances when testing new medicines. They say it would be better to compare new drugs to existing drugs. That way, a study would show if the new drug is more effective.
This VOA Special English Health Report was written by Nancy Steinbach. Our reports are on the Web at WWW.testbig.com. This is Gwen Outen.