Patients' reactions to finding out they were in the placebo group (created 2005-05-11)

This article was originally published on my old website, but it seems to have disappeared. I'm reproducing it here with a few revisions.

A lot of people have written a lot of things about the use of placebos in research, but one group that hasn't been heard from nearly enough is the patients themselves. A recently published article has changed that trend.

This study was a semi-structured questionnaire given to 42 patients who received placebo in a study of corticosteroid for heel pain. The authors cite a publication that found that more than half of the research studies did not tell anything to their placebo patients after the study ended and that the most common reason given is that such a thought had never even occurred to the researchers.

This is rather sad when you think about it. Patients who participate in research give us a wonderful gift. They cede authority over what treatment they will get. And they give this authority, not to their doctor, but to a random device like a coin flip. These volunteers are willing to endure a fair amount of inconvenience, possibly endure additional pain (for getting extra blood samples, for example), and maybe even suffer an increased level of risk in the study. One way you can show your gratitude to them is by letting know at the earliest possible moment what treatment they did receive. Don't do this during the study, of course, because that destroys all the benefits of blinding and ruins the rationale for using a placebo group in the study. But after the study is over, you should offer this information.

The authors do cite one example, though, where some patients were on a placebo for treatment for depression. They responded well, as you might expect from the placebo effect, but when they were told afterwards that they were on a placebo, most of them relapsed. In another trial, patients who received a placebo surgery were angry when they found out afterwards and demanded the active surgery, even though the research showed that the active surgery was no better than placebo.

This webpage was originally published at the StATS website, but is updated here to add new information. The original page can be found at www.childrens-mercy.org/stats/weblog2005/PatientsReactions.asp.

Need more information? I have a page with general help resources. You can also browse for pages similar to this one at Category: Placebos in research.