title: Defining publication bias: protocol for a systematic review of highly cited articles and proposal for a new framework.
abstract: BACKGROUND
  Selective publication of studies, which is commonly called publication bias, is widely recognized. Over the years a new nomenclature for other types of bias related to non-publication or distortion related to the dissemination of research findings has been developed. However, several of these different biases are often still summarized by the term 'publication bias'.
  
  
  METHODS
  As part of the OPEN Project (To Overcome failure to Publish nEgative fiNdings) we will conduct a systematic review with the following objectives:- To systematically review highly cited articles that focus on non-publication of studies and to present the various definitions of biases related to the dissemination of research findings contained in the articles identified.- To develop and discuss a new framework on nomenclature of various aspects of distortion in the dissemination process that leads to public availability of research findings in an international group of experts in the context of the OPEN Project.We will systematically search Web of Knowledge for highly cited articles that provide a definition of biases related to the dissemination of research findings. A specifically designed data extraction form will be developed and pilot-tested. Working in teams of two, we will independently extract relevant information from each eligible article.For the development of a new framework we will construct an initial table listing different levels and different hazards en route to making research findings public. An international group of experts will iteratively review the table and reflect on its content until no new insights emerge and consensus has been reached.
  
  
  CONCLUSIONS
  Results are expected to be publicly available in mid-2013. This systematic review together with the results of other systematic reviews of the OPEN project will serve as a basis for the development of future policies and guidelines regarding the assessment and prevention of publication bias.
authors.affiliation: Center for Pediatric Clinical Studies, University Children's Hospital Tuebingen, Frondsbergstr. 23, 72070, Tuebingen, Germany.
authors.forename: Katharina Felicitas
authors.initials: KF
authors.lastname: Müller
authors.forename: Matthias
authors.initials: M
authors.lastname: Briel
authors.forename: Alexandra
authors.initials: A
authors.lastname: D'Amario
authors.forename: Jos
authors.initials: J
authors.lastname: Kleijnen
authors.forename: Ana
authors.initials: A
authors.lastname: Marusic
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Wager
authors.forename: Gerd
authors.initials: G
authors.lastname: Antes
authors.forename: Erik
authors.initials: E
authors.lastname: von Elm
authors.forename: Britta
authors.initials: B
authors.lastname: Lang
authors.forename: Edith
authors.initials: E
authors.lastname: Motschall
authors.forename: Viktoria
authors.initials: V
authors.lastname: Gloy
authors.forename: Guido
authors.initials: G
authors.lastname: Schwarzer
authors.forename: Doug
authors.initials: D
authors.lastname: Altman
authors.forename: Joerg J
authors.initials: JJ
authors.lastname: Meerpohl
authors.forename: Dirk
authors.initials: D
authors.lastname: Bassler
mesh_terms: D022126:Access to Information; D015982:Bias; D032921:Consensus; D057225:Data Mining; D006801:Humans; D033181:Information Dissemination; D015201:Meta-Analysis as Topic; D017594:Publication Bias; D012107:Research Design; D000078202:Systematic Reviews as Topic; D009626:Terminology as Topic