MedPage Today
Originally Published March 23, 2012
Several negative studies of second-generation antipsychotic drugs were never published, leading to an exaggerated portrayal of the agents' effectiveness in the scientific literature, researchers said.
Of 24 registration trials involving eight products submitted to the FDA, four went unpublished in medical journals -- three of which found that the study drug's efficacy was equivalent to placebo or inferior to an active comparator, according to Erick H. Turner, MD, of Oregon Health and Science University in Portland, and colleagues.
Moreover, five of the 20 published trials "showed some evidence of outcome reporting bias," the researchers wrote online in PLoS Medicine.
Turner and colleagues also noted that the scale of the publication bias was relatively modest -- exaggerating the drugs' effectiveness relative to placebo or active comparators by a nonsignificant 8%. The weighted-average effect size in the published trials was 0.47 (95% CI 0.40 to 0.54), which declined only to 0.44 (95% CI 0.37 to 0.50) when the unpublished trials were included.
The research paper is below
Publication Bias in Antipsychotic Trials