Price matters when it comes to what people believe will help heal them, according to a new study that has received widespread media attention. The study found that high-priced placebos are more effective than cheaper placebos.

A placebo is a harmless, "fake" medicine that is taken by someone who believes that it is real. Hundreds of scientific studies have proven the so-called "placebo effect" — that placebos can be an effective treatment for many illnesses. While we do not know why this is, it seems that simply believing that a medicine will improve your health can actually make it work.

This recent study has shown not only that placebos can be effective, but that high-priced placebos are more effective than placebos that cost much less — even when their ingredients are identical.

Perhaps, we should not be so surprised. After all, we know the placebo effect is real and it is an established economic principle that consumers will attribute greater value to a product simply because it costs more.

The randomized, blinded study, in which 82 healthy volunteers were given what they were told was a new opioid and then asked to rate its effect as a painkiller, was conducted by a team led by Dan Ariely, Ph.D., of the Massachusetts Institute of Technology and reported in the March 5 issue of the Journal of the American Medical Association. The volunteers were all given the same placebo, but some were told that it cost $2.50 a pill and others were told that the cost was 10 cents a pill.

Those who thought they were taking the expensive pill reported significantly greater pain reduction than those who thought they were getting the cheaper pill. Dr. Ariely said the finding is part of a range of human responses to what are essentially marketing factors. This study might also explain why some patients insist that generic drugs are less effective than brand-name products.

A possible application of these findings, Ariely added, would be in the case of medicines that are offered to patients at a discounted price. "Maybe we don't want to advertise that its discounted," he said. The idea being, as the study showed, that people will think a medicine is less effective if its price has been cut.

With pain, Dr. Ariely said, "if you expect it to be worse, it could be worse. So what can we do in the marketplace so people don't expect it to be worse?" He suggested that doctors might want to consider the placebo effect when they explain the benefits of medications to patients, avoiding language that might cause them to regard a drug as cheap or second-rate.

Dr. Ariely pointed out that most scientific studies, the placebo effect is considered a nuisance that must be discounted in order to prove the effectiveness of a drug or treatment approach. "Do we really want to consider it a nuisance variable or do we want to think about how to use it?" he asked.