title: Summarizing systematic reviews: methodological development, conduct and reporting of an umbrella review approach.
abstract: OBJECTIVE
  With the increase in the number of systematic reviews available, a logical next step to provide decision makers in healthcare with the evidence they require has been the conduct of reviews of existing systematic reviews. Syntheses of existing systematic reviews are referred to by many different names, one of which is an umbrella review. An umbrella review allows the findings of reviews relevant to a review question to be compared and contrasted. An umbrella review's most characteristic feature is that this type of evidence synthesis only considers for inclusion the highest level of evidence, namely other systematic reviews and meta-analyses. A methodology working group was formed by the Joanna Briggs Institute to develop methodological guidance for the conduct of an umbrella review, including diverse types of evidence, both quantitative and qualitative. The aim of this study is to describe the development and guidance for the conduct of an umbrella review.
  
  
  METHODS
  Discussion and testing of the elements of methods for the conduct of an umbrella review were held over a 6-month period by members of a methodology working group. The working group comprised six participants who corresponded via teleconference, e-mail and face-to-face meeting during this development period. In October 2013, the methodology was presented in a workshop at the Joanna Briggs Institute Convention. Workshop participants, review authors and methodologists provided further testing, critique and feedback on the proposed methodology.
  
  
  RESULTS
  This study describes the methodology and methods developed for the conduct of an umbrella review that includes published systematic reviews and meta-analyses as the analytical unit of the review. Details are provided regarding the essential elements of an umbrella review, including presentation of the review question in a Population, Intervention, Comparator, Outcome format, nuances of the inclusion criteria and search strategy. A critical appraisal tool with 10 questions to help assess risk of bias in systematic reviews and meta-analyses was also developed and tested. Relevant details to extract from included reviews and how to best present the findings of both quantitative and qualitative systematic reviews in a reader friendly format are provided.
  
  
  CONCLUSIONS
  Umbrella reviews provide a ready means for decision makers in healthcare to gain a clear understanding of a broad topic area. The umbrella review methodology described here is the first to consider reviews that report other than quantitative evidence derived from randomized controlled trials. The methodology includes an easy to use and informative summary of evidence table to readily provide decision makers with the available, highest level of evidence relevant to the question posed.
authors.affiliation: 1The Joanna Briggs Institute, University of Adelaide, Adelaide, South Australia 2School of Nursing, University of Wollongong; Centre for Research in Nursing and Health, St George Hospital, Sydney, Australia 3Queen's Joanna Briggs Collaboration, Queen's University School of Nursing, Kingston, Ontario, Canada 4Northeast Institute for Evidence Synthesis and Translation Rutgers, University School of Nursing Newark, New Jersey, USA 5Monash University, School of Rural Health, Victoria, Australia 6Thailand Centre for Evidence Based Nursing, Midwifery, and Health Science: a Collaborating Centre of JBI, Faculty of Nursing, Chiang Mai University, Chiang Mai, Thailand.
authors.forename: Edoardo
authors.initials: E
authors.lastname: Aromataris
authors.forename: Ritin
authors.initials: R
authors.lastname: Fernandez
authors.forename: Christina M
authors.initials: CM
authors.lastname: Godfrey
authors.forename: Cheryl
authors.initials: C
authors.lastname: Holly
authors.forename: Hanan
authors.initials: H
authors.lastname: Khalil
authors.forename: Patraporn
authors.initials: P
authors.lastname: Tungpunkom
mesh_terms: D015982:Bias; D036262:Empirical Research; D019317:Evidence-Based Medicine / Q000458:organization & administration* / Q000592:standards; D017408:Guidelines as Topic; D006801:Humans; D015201:Meta-Analysis as Topic; D012107:Research Design / Q000592:standards*; D012196:Review Literature as Topic; D000078202:Systematic Reviews as Topic