Derived from the Latin word meaning “I shall please,” a placebo is a simulated medical intervention that can produce an actual or even perceived improvement. This improvement is called a “placebo effect.” In medical research, placebos depend upon controlled and measured deception, usually appearing in the form of inert tablets, sham surgery, and other false information. [audio:http://hospitalstay.com/wp-content/uploads/2010/10/Black-Eyed-1.mp3|titles=Black-Eyed]

A new article appearing in the Annals of Internal Medicine entitled “What’s in Placebos: Who Knows?” explores the lack of scientific control in preparing this common element found in many controlled scientific studies. The reviewers in this study independently abstracted data from the introduction and methods sections of identified articles, recording treatment type (pill, injection, or other) and whether placebo composition was stated. Any discrepancies were resolved by consensus.

According to the author, Beatrice Golomb, MD, PhD, associate professor of medicine at the University of California, San Diego School of Medicine, this standard has a fundamental problem. “[T]here isn’t anything actually known to be physiologically inert. On top of that, there are no regulations about what goes into placebos, and what is in them is often determined by the makers of the drug being studied, who have a vested interest in the outcome. And there has been no expectation that placebos’ composition be disclosed. At least then readers of the study might make up their own mind about whether the ingredients in the placebo might affect the interpretation of the study.”

In a couple of letters sent to the journal Nature fifteen years ago, Dr. Golomb raised similar issues: “A positive or negative effect of the placebo can lead to the misleading appearance of a negative or positive effect of the drug,” she said. “And an effect in the same direction as the drug can lead a true effect of the drug to be lost. These concerns aren’t just theoretical. Where the composition has been disclosed, the ingredients of the placebo have in some instances had a likely impact on the result of the study — in either direction (obscuring a real effect, or creating a spurious one). In the cases we know about, this is not because of any willful manipulation, but because it can in fact be difficult to come up with a placebo that does not have some kind of problem.”

The study concluded that placebos were seldom described in randomized, controlled trials of pills or capsules. Since the very nature of the placebo can significantly influence study outcomes, the authors conclude that placebo formulation should be disclosed reports where placebos are used.