Setting a placebo standard?

The standard placebo-controlled trial is being called into question. Once considered the gold standard of clinical comparative analysis, the very idea is now being treated with skepticism. Could it be there is no standard behind the standard?

Basically the belief is that in order to test whether a treatment is effective, a group participating in the treatment needs to be compared to a similar group not participating in the treatment. No one in the group knows who is in which group. In the case of medications, participants are randomly selected to either take the test drug or an inert drug called a placebo.

According to the research paper’s author, Beatrice Golomb, MD, PhD, associate professor of medicine at the University of California, San Diego School of Medicine, there is a big flaw: “There 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.”

This has all the makings of a potential conspiracy among pharmas or a movie of the week. She continued, “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 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 team discovered that the contents of the placebo in research cases are only disclosed 10% of the time. “How often study results are affected by what’s in the placebo is hard to say because as this study showed, most of the time we have no idea what the placebo is,” Golomb summarized. This is not reassuring and hopefully pressure will be placed on the appropriate people for more transparency in the placebo process.

Source: University of California-San Diego, ScienceDaily