What dissemination bias really means and how we can tackle it

Article type
Authors
Bassler D1, Mueller K2, Briel M3, Kleijnen J4, Marusic A5, Wager E6, Antes G7, von Elm E8, Altman D9, Meerpohl J7
1Department of Neonatology, University Hospital Zuerich, Switerzland
2Center for Pediatric Clinical Studies, University Children's Hospital Tuebingen, Germany
3Basel Institute for Clinical Epidemiology and Biostatistics, Switzerland
4Schoof for Public Health and Primary Care, Maastricht University, The Netherlands
5Department of Research in Biomedicine and Healt, University of Split School of Medicine, Croatia
6Sideview, United Kingdom
7German Cochrane Centre, Germany
8Cochrane Switzerland, Switzerland
9Centre for Statistics in Medicine, University of Oxford, United Kingdom
Abstract
Introduction: Systematic reviews of high-quality randomized controlled trials provide a valid summary of research findings, and are therefore crucial to evidence-based health care decision-making. However, it is not always possible to retrieve all existing evidence for a given topic, as many studies never reach publication. Selective publication of studies based on the nature and direction of the results, commonly called ‘publication bias’, is widely recognized but not defined in a consistent way. Within the international OPEN project (To Overcome failure to Publish nEgative fiNdings) we aimed to develop a consistent and comprehensive approach to defining (non-)dissemination of research findings in an international group of experts.
Development of the OPEN framework: In a first step, we performed a scoping review of definitions of the term ‘publication bias’ in highly cited publications. In a second step we proposed a draft regarding the issues that need to be considered when exploring possible biases due to selective dissemination of research findings. We then circulated the draft to all the co-authors and, in a third step, to all members of the OPEN consortium (an international group of experts). Experts reviewed the draft and, if they felt appropriate, provided feedback regarding the issues we identified or contributed with other insights. We continued this process until consensus was reached.
OPEN framework of (non-)dissemination of research findings: We propose a comprehensive and consistent approach to the issue of (non-) dissemination of research findings which, in part, is focusing on the various key groups involved in the knowledge generation and dissemination process. The proposed approach includes three parts: 1) issues that need to be considered when exploring possible biases due to selective dissemination of research findings (what?); 2) stakeholders who could assume responsibility for the various stages of conducting a clinical trial and disseminating of clinical trial documents (who?); and 3) motivations that may lead the various players to selectively disseminate findings, thereby introducing bias in the dissemination process (why?).