Placebo Effect Study
By Nancy SteinbachThis is the VOA Special English SCIENCE REPORT.
Many Special English Science Reports discuss medical studies that test the effect of a new drug. Usually, a large number of people is divided into two groups. One group takes the medicine being tested. The other takes an inactive substance called a "placebo."
The word "placebo" is Latin for "I shall please." Placebo pills are usually made of sugar. No one knows which group is taking which substance. In such testing, the drug must perform better than the placebo to prove that it is effective.
However, the people who take the placebos often report improvements in their health. This is known as "the placebo effect" pain that is eased or stopped by an inactive substance. Doctors have reported that the placebo effect can be used in treatment. For example, a doctor tells a patient that a new drug will stop her pain. The pill is only sugar. But the patient does not know that. She takes the pill and says the pain is gone.
Belief in this placebo effect began with a medical study published in Nineteen-Fifty-Five. It said treatment with a placebo made patients feel better thirty-five percent of the time. Experts think this is because the patients believed they were getting an effective treatment. A new study, however, questions the placebo effect.
Danish researchers at the University of Copenhagen and the Nordic Cochrane Center did the new study. They reported the results in The New England Journal of Medicine. They examined more than one-hundred studies from around the world involving placebos. More than eight-thousand people were involved in the studies. They suffered from among forty different medical disorders.
The researchers found little evidence of healing as the result of placebo use. They found no effect at all on measurements such as blood pressure or cholesterol levels. They found evidence of a placebo effect only when patients reported feeling better.
The researchers said this improvement may have had nothing to do with the placebo at all. Or the patients may have been trying to please their doctors. The researchers said placebos should be used only for research purposes and not for treatment.
Experts say more studies are needed to show whether or not the placebo effect exists.
This VOA Special English SCIENCE REPORT was written by Nancy Steinbach.