Overview of reviews in child health: evidence synthesis and the knowledge base for a specific population

Abstract

Background Overviews of reviews are an evolving form of evidence synthesis. The Cochrane Child Health Field has been producing overviews since 2006, during which time the methods that have been used have changed, both due to the development of guidance within The Cochrane Collaboration and to the decisions made by individual author teams. This paper studies the first 29 overviews published in EBCH. Objectives To describe some aspects of the approaches taken in EBCH overviews to producing evidence syntheses relevant to the healthcare needs of children; to highlight the contribution that overviews can make to the knowledge base for treatment for a particular population. Methods Data was extracted on: whether the overview included systematic review (SR) data only, or also data from individual trials not present in the included SRs; name(s) of the Cochrane Review Group (CRG) that prepared the included SRs; topics of the overviews as compared to the topics of the included reviews; age‐subgroup analyses presented in the overviews. Results In 23 overviews, all published in 2012, the authors included trial data as well as SR data; two overviews addressed conditions not explicitly addressed by the included reviews; three overviews included pre‐specified age‐subgroup analyses. Discussion The aim of clinical relevance has been achieved by means such as: drawing from reviews produced by multiple CRGs; using SR evidence to explore clinically relevant topics that may not match exactly with the topics covered by the SRs; ensuring that the evidence in overviews is as up to date as possible by redoing searches and including trials not incorporated in the included SRs; and, where permitted by the data, using age‐subgroup analyses to present the data in a way which matches the stages of childhood development. Conclusion Overview authors are dependent on the nature of the data and methods reported in the included SRs. This suggests a need for further study about how SRs could be conducted in order to facilitate the conduct of overviews. Copyright © 2013 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd. The Cochrane Collaboration

What guidance is available for researchers conducting overviews of reviews of healthcare interventions? A scoping review and qualitative metasummary

“…Lastly, the guidance included in this scoping review came from documents that explicitly intended to provide methods guidance to readers: the methods presented here do not come from the actual methods used in published overviews. However, discussions with overview authors [13] and critical appraisal of published overviews [4, 5, 38, 39] indicates that the guidance and challenges in this scoping review are congruent with overview authors’ experiences.…”

Preventing Child and Adolescent Anxiety Disorders: Overview of Systematic Reviews

“…For example, Smith et al [43] did not discuss the inclusion of primary studies. Thomson et al, [42] in contrast, advocated for OSR authors to ensure the evidence reviewed is up-to-date. Pieper et al [40] noted that 5% of the 126 overviews included in his systematic review of overview quality included a search for primary studies and stated that little empirical evidence is available to guide decisions about when and how to update reviews.…”

Selecting and implementing overview methods: implications from five exemplar overviews

“…Overviews of systematic reviews are an increasingly popular method of evidence synthesis [1, 2], and there are a growing number of resources, including guidelines, recommendations, descriptions and systematic reviews, relating to overview methods [2–6]. While there are some areas of agreement in relation to optimal overview methods, particularly in the early stages of overview completion [5], there remains considerable uncertainty around some key areas of methodology [3, 5, 7, 8] and a need for clearer standards and reporting guidance, supported by research evidence, to enhance methodological quality of overviews [1–3, 5, 6].…”

“…While there are some areas of agreement in relation to optimal overview methods, particularly in the early stages of overview completion [5], there remains considerable uncertainty around some key areas of methodology [3, 5, 7, 8] and a need for clearer standards and reporting guidance, supported by research evidence, to enhance methodological quality of overviews [1–3, 5, 6]. …”