Placebo effect: the ultimate complementary medicine
If someone advocates a complementary or alternative treatment, the first question to ask is not, “Is it effective?”
No, the first question is, “In clinical trials, how did treatment X compare to the ‘placebo effect’ in the same disease?”
To understand why, let’s start by defining terms.
- Placebo: an innocuous treatment
- Placebo effect: response to placebo
In one study that looked at pain, high blood pressure, and asthma, 30% to 40% of patients got relief taking a placebo.That’s right, about 1/3 of any population will have a positive response to placebo.
Another study of angina pectoris treated surgically reported an 80% response to the placebo procedure (cutting the skin). But only a 40% response in patients actually operated on. In other words: the placebo effect was better than surgery.
How can this be?
There seems to be an interaction between the predisposition of the doctor and patient to believe the treatment will work.
- People who take placebos diligently do better than those who take them occasionally
- Placebo injections work better than placebo pills
- Brand name placebos relieve pain better than generic placebos
- Blue placebos are better sedatives than red ones – except for Italian men, for whom the opposite is true
And
- The more convinced a doctor is that a drug or a placebo will work, the more likely that it really will.
The bottom line?
View anecdotal reports of success cautiously. Since the typical placebo response is 30%, it’s pretty easy for an “enthusiastic” doctor to treat a small number of people, get a few positive responses, and then use just those cases as “proof” of efficacy.
Now, you know better. The first question is always “In clinical trials, how did treatment X compare to the ‘placebo effect’ in the same disease?”
8/2/06 13:54 JR