title: What you see depends on where you're looking and how you look at it: publication bias and outcome reporting bias.
abstract: Study publication bias is the decision to publish or not publish a study based on its results. Compared to unpublished work, published studies are more likely to have positive or statistically significant findings. Outcome reporting bias is opting to publish only a subset of the original variables recorded for a study, such that the inclusion of the variables in the published work is selectively based on the results. Statistically significant results have a higher likelihood of being fully reported compared to nonsignificant results, and a significant proportion of published articles describe outcome variables or data analyses that differ from the pre-specified trial protocol as originally conceived. Recognition that publication bias and outcome reporting bias contribute to a distorted perception of drug effects-inflated estimates of efficacy and underreporting of adverse events-has led to the development and expansion of publicly accessible databases that contain transparent information about clinical trials and their results.
authors.affiliation: University of Pittsburgh School of Medicine, Western Psychiatric Institute and Clinic, Pittsburgh, Pennsylvania 15213, USA. HowlandRH@upmc.edu
authors.forename: Robert H
authors.initials: RH
authors.lastname: Howland
mesh_terms: D015982:Bias; D002986:Clinical Trials as Topic; D016208:Databases, Factual; D004341:Drug Evaluation; D005060:Europe; D006801:Humans; D017594:Publication Bias; D012042:Registries; D014481:United States