Posted by SLS on January 18, 2008, at 17:11:54
Hi.
My impression is that this behavior has been condoned by the FDA for many years such that it became accepted as standard practice by the pharmaceutical companies.
- Scott------------------------------------------------
Study Identifies Bias in Favor of Publishing Positive Antidepressant TrialsMedscape Medical News 2008. © 2008 Medscape
These findings are published in the January 17 issue of the New England Journal of Medicine.
January 17, 2008 A study of Food and Drug Administration (FDA)registered clinical trials of 12 antidepressants found a bias toward publication of positive results. Almost all studies viewed by the FDA as positive were published. The clinical trials that the FDA deemed negative or questionable were largely not published or, in some cases, were published as positive outcomes.
For each of the 12 drugs, at least 1 study was not published or was reported in the literature as positive despite a conflicting judgment by the FDA.
The overall effect size of the antidepressants (vs placebo) that was reported in the published literature was nearly one-third larger than the effect size for these agents that was derived from FDA data.
"Selective reporting of clinical-trial results may have adverse consequences for researchers, study participants, healthcare professionals, and patients," they conclude.
Evidence-Based or Biased Evidence?
"You might get the impression from the published literature that [these drugs] are consistently effective; however, the outcome of this study is that they are effective, but inconsistently so," lead study author, Eric H. Turner, MD, from Oregon Health and Science University, in Portland, Oregon, told Medscape Psychiatry.
"Evidence-based medicine is valuable to the extent that the evidence is complete and unbiased," he noted, adding that selective publication of clinical trials can alter the apparent risk/benefit ratio of drugs, which can affect prescribing decisions.
The current study sought to examine how accurately the published literature conveys data on drug efficacy to the medical community.
The team identified the phase 2 and 3 clinical-trial programs for 12 antidepressants approved by the FDA between 1987 and 2004, which involved 12,564 adult patients. They also determined whether the FDA judged the studies to be positive or negative with respect to primary end points.
To identify matching study publications, the researchers conducted a systematic literature search and contacted the sponsors of the drug studies.
Among the 74 FDA-registered antidepressant studies, the team found that 23 trials (31%) had not been published.
Among the 38 of 74 studies (51%) that the FDA deemed to be positive, 37 were published.
The remaining 36 studies (49%) were deemed to be either negative (24 studies) or questionable (12). Of these 36 studies, 22 were not published, 11 were published as positive, and 3 were published as negative.
poster:SLS
thread:807465
URL: http://www.dr-bob.org/babble/20080114/msgs/807465.html