Understanding the Limitations of Clinical Data

In my first blog entry, I stated my interest in science-based medicine (SBM). Part of an SBM approach to treating patients is not just to be on the lookout for quackery, scams, etc., but also to make sure our own house is in order. I mentioned the importance of clinical trial data in guiding our treatment. However, it is important to understand the potential limitations of our ability to have access to all of the relevant data. 

I would strongly recommend to you the excellent article Turner, E., Matthews, A., Linardatos, E., Tell, R., Rosenthal, R. (2008). Selective Publication of Antidepressant Trials and Its Influence on Apparent Efficacy New England Journal of Medicine, 358 (3) 252-260. This article reviewed 74 phase-2 and -3 clinical trials for 12 antidepressants that were approved by the FDA between 1987 and 2004 involving 12,564 patients. 

In this review, they found that 97% of positive, but only 12% of negative studies were published. Of the 12,564 patients in these studies, data for 99% of patients in positive, but only 6% of negative studies were published. 

In fairness, this is not always some nefarious plot to suppress information that does not support the efficacy of the medication in question. It is harder to get a study published that fails to show a separation from placebo. Also, there are realistic intellectual property  concerns that affect the decision to make this data available. 

There has been increasing pressure on the pharmaceutical industry for greater transparency in reporting the results of all clinical trials. In 2004, Eli Lilly announced the launch of a clinical trials registry database that provided information on all of their trials. Earlier this year in February 2013, Glaxo SmithKline announced that they also were making available data from all of their clinical trials as part of the All Trials campaign (www.alltrials.net). Clinicaltrials.gov is also an excellent resource. 

Our ability to understand the relevant literature is dependent on access to all of the literature as well as the tools to critically evaluate these studies. It reminds me of a recent quote I saw. 

Science:

If you don't make mistakes, you're doing it wrong.

If you don't correct your mistakes, you're doing it really wrong.

If you can't accept that you're mistaken, you're not doing it at all.

Chris Bojrab, MD, is the president of Indiana Health Group, the largest multidisciplinary behavioral health private practice in Indiana, established in 1987. He is a board certified psychiatrist and a Distinguished Fellow of the American Psychiatric Association who treats child, adolescent, adult, and geriatric patients. His areas of interest include psychopharmacology, sleep disorders, and gambling addiction. For more information and disclosures, visit www.chrisbojrabmd.com

The views expressed on this blog are solely those of the blog post author and do not necessarily reflect the views of Psych Congress Network or other Psych Congress Network authors.