Dynamic Chiropractic

Dynamic Chiropractic Facebook Twitter
Dynamic Chiropractic
Advanced Search
Wellness Blog
Dynamic Chiropractic
Dynamic Chiropractic PracticeINSIGHTS
Current Graphic

A Follow-Up on Publication Bias

In my role as Human Protections Administrator at Palmer College of Chiropractic I am the first person to review a proposed project’s institutional review board (IRB) application. When we conduct clinical trials, we need to reveal to our patients the risks and benefits of their participation. While the risks are often well understood, the benefits are not. We cannot guarantee that anyone who enters a trial will receive a benefit; if we could, we would be violating a concept known as “clinical equipoise” and there would obviously be no need to do the trial at all, since we would already know the answer. As a result, what most researchers will put down as the benefit will be words to the effect that the patient may receive no personal benefit at all but will help contribute to scientific knowledge. That is, their participation, with the risk they accept, will be used to help inform future directions of treatment or other.

But now consider the impact of a research team not publishing the results of their research. They would, in fact, be not telling the truth to the participant. If the results are never published, no one can use the information from the study for any reason whatsoever, and the participant would have accepted all the risk with no possible benefit. Other researchers are not able to look at the data- because the data was never published. We know this as publication bias, which is a real and growing problem in science.

Solutions have been offered to help prevent this from occurring. That is why you will see a ClinicalTrials.gov identifier appended to all the clinical trials you see published in major chiropractic journals. The government has required all federally (and other) funded research to register with ClinicalTrials.gov (or other repositories), so that an interested person can identify if a study on a particular topic has been conducted- this is also important since funds are limited (so why do a study if it is already being done?), and we also wish to limit risk to participants. But it has been found that in some circumstances up to 30% of trials registered in clinicaltrials.gov have never shared the results of their study, even as late as 4 years after completion of the project (1).

A new paper in JAMA (2) discusses a newly proposed rule from the US Department of Health and Human Services (3) to implement a rule from the Food and Drug Administration Amendment Act of 2007. This would require sharing of data from specified groups of clinical trials, notably of regulated drugs and devices. While this has been law for some time, the proposal aims to extend the scope of law. NIH is looking to increase transparency in research. It has not been enough to require listing in ClinicalTrials.gov and hidden data (especially if it conceals negative results) can seriously skew public review of what data can be found- usually in favor of an intervention.

This is important. And let me give a novice researcher a research idea: Go into ClinicalTrials.gov, locate all the chiropractic projects, and see how many have later been published. I do not know the answer- and perhaps we will shine. But it may be we will not. Let’s rectify that.


  1. Saito H, Gill J. How frequently do the results from completed US clinical trials enter the public domain?- a statistical analysis of the ClinicalTrials.gov database. PLoS One 2014:9(7):e101826
  2. Hudson KA, Collins FS. Sharing and reporting the results of clinical trials. JAMA 2015;313:355-356
  3. Notice of porposed rule making. http://ofr.gov/OFRUpload/OFRData/2014-26197_PI.pdf. Accessed February 16, 2015

Leave a Reply