title: Different roles of electromagnetic field experts when giving policy advice: an expert consultation.
abstract: BACKGROUND
  The overall evidence for adverse health effects of electromagnetic fields (EMF) at levels of exposure normally experienced by the public is generally considered weak. However, whether long-term health effects arise remains uncertain and scientific policy advice is therefore given against a background of uncertainty. Several theories exist about different roles that experts may take when they provide advice on complex issues such as EMF. To provide empirical evidence for these theories, we conducted an expert consultation with as main research question: What are the different roles of EMF experts when they provide policy advice?
  
  
  METHODS
  Q methodology was used to empirically test theoretical notions on the existence and determinants of different expert roles and to analyze which roles actually play out in the domain of EMF. Experts were selected based on a structured nominee process. In total 32 international EMF experts participated. Responses were analyzed using Principal Component Analysis and for the open questions we used Atlas.ti.
  
  
  RESULTS
  Four expert roles were found. Most striking differences between the four roles are whether experts consider current EMF policies adequate or not, whether additional -precautionary- measures are needed, and how experts view their position vis-à-vis policymakers and/or other stakeholders.
  
  
  CONCLUSIONS
  This empirical study provides support for the so far mainly theoretical debate about the existence of different roles of experts when they give policy advice. The experts' assessment of the degree of uncertainty of the issue turned out to be highly associated with their role. We argue that part of the controversy that exists in the debate regarding scientific policy advice on EMF is about different values and roles.
authors.affiliation: Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands. pita.spruijt@rivm.nl.|Centre for Sustainability, Environment and Health, National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands. pita.spruijt@rivm.nl.
authors.forename: Pita
authors.initials: P
authors.lastname: Spruijt
authors.affiliation: Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands.
authors.forename: Anne B
authors.initials: AB
authors.lastname: Knol
authors.affiliation: Institute for Environmental Studies, VU University Amsterdam, Amsterdam, The Netherlands.|Department of Science, Technology, Engineering and Public Policy, University College London, London, UK.
authors.forename: Arthur C
authors.initials: AC
authors.lastname: Petersen
authors.affiliation: Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands.|Centre for Sustainability, Environment and Health, National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands.
authors.forename: Erik
authors.initials: E
authors.lastname: Lebret
mesh_terms: D004574:Electromagnetic Fields / Q000009:adverse effects*; D004781:Environmental Exposure / Q000009:adverse effects*; D005104:Expert Testimony; D005260:Female; D006291:Health Policy; D006801:Humans; D008297:Male; D008875:Middle Aged; D024382:Professional Role; D018570:Risk Assessment