What is a Placebo?
A placebo is an inactive medication or medical treatment which yields no medical benefit. A placebo is used in a clinical trial to compare its lack of effect to the actual effect of a medical treatment being studied.
That's how it's supposed to work. However, the placebo itself can elicit a response, known as a "placebo response". The placebo response occurs when a patient believes they are improving because they know they are receiving medical treatment, though no true improvement in symptoms occurs. There is also evidence that actual physiologic changes can occur from receving placebo.
Is Every Placebo Alike?
The effect of a sham acupuncture device was compared to the effect of a placebo pill. The purpose of the study was to determine if the medical device provoked a different response than the placebo pill. The study involved 270 participants and results were published in the British Medical Journal.
Placebo Study: Two Phases
All of the 270 participants suffered with chronic arm pain. In the first phase of the study, 135 study participants were treated with the sham acupuncture device and the other 135 participants were treated with a placebo pill for a 2 week period. It was concluded by researchers that the placebo device did not have a stronger effect than the placebo pill.
In the second phase of the study, researchers randomly assigned half of the participants to a sham acupuncture procedure versus real acupuncture for four more weeks. The other half of the participants were randomized to receive either a placebo pill or a real pain pill for six more weeks.
Results From Placebo Study
Results from the second phase revealed that participants receiving sham acupuncture reported more significant decrease in pain and symptoms than the participants who received placebo pills. Researchers concluded that:
- the subjective reports from study participants show that the placebo used impacts placebo effect.
- objective assessments such as grip strength revealed no difference.
In the study, using a medical device seemed to impact the patient response more than merely taking a pill. Other studies have begun which will further examine the effect of placebo in clinical trials.
All Placebos Not Created Alike, Newswise
Sham device v inert pill: randomised controlled trial of two placebo treatments, British Medical Journal