From Qualitative Reviews to Umbrella Reviews

The volume of health-care literature is growing at an increasing rate, with a huge amount of studies difficult to process. Therefore, we need tools or techniques to synthesize the information to help us in clinical decision-making. In fact, the available body of evidence ranges from single studies to umbrella reviews. In this scenario, evidence-based clinical decision-making requires knowing what type of evidence to use in every situation. However, a prerequisite for optimal decision-making is a greater understanding by professionals of the different techniques used to analyse their strengths, limitations and utilities. The purpose of this chapter is to take a journey from qualitative reviews to umbrella reviews. We start the tour on a fundamental point: term definitions, showing the variability among different authors. We go on to describe the differences, advantages, disadvantages and uses of different types of evidence, from individual studies to the ‘more specific methods’ for knowledge synthesis, both qualitative and quantitative syntheses (systematic reviews, meta-analysis, network meta-analysis). Finally, in the last part of our journey, we compare the strengths and weaknesses of different evidence synthesis methods from the more traditional or specific to the more general or broader reviews (umbrella reviews, overviews of reviews, meta-epidemiologic reviews). Systematic reviews are at the top of the evidence pyramid. However, the number of systematic reviews published is increasing at a high rate, and decision-makers need to evaluate more evidence to answer their questions. Systematic reviews of existing systematic reviews, known as umbrella reviews, provide an overall examination of the body of information that is available for a given topic. Despite the limitations and weaknesses of tools to appraise and synthesize evidence, systematic reviews and umbrella reviews, including overviews of reviews and meta-epidemiological studies, continue to be the best tool for an approximation to the truth, in evidence-based terms.

[1]  P. Glasziou,et al.  Can we rely on the best trial? A comparison of individual trials and systematic reviews , 2010, BMC medical research methodology.

[2]  Christopher H. Schmid,et al.  Characteristics of Networks of Interventions: A Description of a Database of 186 Published Networks , 2014, PloS one.

[3]  Hsinchun Chen,et al.  Visualization of large category map for Internet browsing , 2003, Decis. Support Syst..

[4]  M. Clarke,et al.  Methodology in conducting a systematic review of systematic reviews of healthcare interventions , 2011, BMC medical research methodology.

[5]  Denise Thomson,et al.  A Descriptive Analysis of Overviews of Reviews Published between 2000 and 2011 , 2012, PloS one.

[6]  G. Biondi-Zoccai,et al.  In Intensive Care Cardiovascular Anesthesia Review Article the Rough Guide to Systematic Reviews and Meta-analyses , 2022 .

[7]  The Science and Art of Deduction: Complex Systematic Overviews , 2008, Annals of Internal Medicine.

[8]  Joseph C Cappelleri,et al.  Indirect treatment comparison/network meta-analysis study questionnaire to assess relevance and credibility to inform health care decision making: an ISPOR-AMCP-NPC Good Practice Task Force report. , 2014, Value in health : the journal of the International Society for Pharmacoeconomics and Outcomes Research.

[9]  Georgia Salanti,et al.  Indirect and mixed‐treatment comparison, network, or multiple‐treatments meta‐analysis: many names, many benefits, many concerns for the next generation evidence synthesis tool , 2012, Research synthesis methods.

[10]  H. Arksey,et al.  Scoping studies: towards a methodological framework , 2005 .

[11]  John P.A. Ioannidis,et al.  Integration of evidence from multiple meta-analyses: a primer on umbrella reviews, treatment networks and multiple treatments meta-analyses , 2009, Canadian Medical Association Journal.

[12]  Eva Alisic,et al.  Making a difference: towards a method for weighing the evidence in a qualitative synthesis. , 2011, Journal of evaluation in clinical practice.

[13]  C D Naylor,et al.  Meta-analysis and the meta-epidemiology of clinical research , 1997, BMJ.

[14]  P. Glasziou,et al.  Are systematic reviews up-to-date at the time of publication? , 2013, Systematic Reviews.

[15]  W. Hillegass,et al.  Overview, Strengths, and Limitations of Systematic Reviews and Meta-Analyses , 2010 .

[16]  Catrin Tudur Smith,et al.  Assessing key assumptions of network meta‐analysis: a review of methods , 2013, Research synthesis methods.

[17]  J. H. Noble.  Meta-analysis: Methods, strengths, weaknesses, and political uses. , 2006, The Journal of laboratory and clinical medicine.

[18]  Andrew W Lee,et al.  Review of mixed treatment comparisons in published systematic reviews shows marked increase since 2009. , 2014, Journal of clinical epidemiology.

[19]  G. Biondi‐Zoccai,et al.  Which Do You Like Better … a Bowl of Cheerios or a Big Mac? Pros and Cons of Meta-Analyses in Endovascular Research , 2013, Journal of endovascular therapy : an official journal of the International Society of Endovascular Specialists.

[20]  B. Vandermeer,et al.  Systematic reviews, overviews of reviews and comparative effectiveness reviews: a discussion of approaches to knowledge synthesis. , 2014, Evidence-based child health : a Cochrane review journal.

[21]  Huseyin Naci,et al.  Is network meta-analysis as valid as standard pairwise meta-analysis? It all depends on the distribution of effect modifiers , 2013, BMC Medicine.

[22]  Trisha Greenhalgh,et al.  Storylines of research in diffusion of innovation: a meta-narrative approach to systematic review. , 2005, Social science & medicine.

[23]  H. Bastian,et al.  Seventy-Five Trials and Eleven Systematic Reviews a Day: How Will We Ever Keep Up? , 2010, PLoS medicine.

[24]  D. Moher,et al.  Scoping reviews: time for clarity in definition, methods, and reporting. , 2014, Journal of clinical epidemiology.

[25]  J. Ioannidis,et al.  Evolution and Translation of Research Findings: From Bench to Where? , 2006, PLoS clinical trials.

[26]  Jennie Popay,et al.  Qualitative Research and Cochrane Reviews , 2008 .

[27]  Kristian Thorlund,et al.  Reanalyses of randomized clinical trial data. , 2014, JAMA.

[28]  G. Biondi-Zoccai,et al.  A journey into clinical evidence: from case reports to mixed treatment comparisons , 2011, HSR proceedings in intensive care & cardiovascular anesthesia.

[29]  Deborah M Caldwell,et al.  Simultaneous comparison of multiple treatments: combining direct and indirect evidence , 2005, BMJ : British Medical Journal.

[30]  Douglas G Altman,et al.  Statistical methods for assessing the influence of study characteristics on treatment effects in ‘meta‐epidemiological’ research , 2002, Statistics in medicine.

[31]  D. Moher,et al.  Guides for reading and interpreting systematic reviews: I. Getting started. , 1998, Archives of pediatrics & adolescent medicine.

[32]  Kristian Thorlund,et al.  The effects of excluding treatments from network meta-analyses: survey , 2013, BMJ : British Medical Journal.

[33]  R Brian Haynes,et al.  Accessing pre-appraised evidence: fine-tuning the 5S model into a 6S model , 2009, Evidence-based nursing.

[34]  Peter Tugwell,et al.  Knowledge synthesis to improve practice requires up-to-date definitions, content, methods, and techniques. , 2014, Journal of clinical epidemiology.

[35]  S. Michie,et al.  Intervention Synthesis: A Missing Link between a Systematic Review and Practical Treatment(s) , 2014, PLoS medicine.

[36]  Kristian Thorlund,et al.  How to use an article reporting a multiple treatment comparison meta-analysis. , 2012, JAMA.

[37]  Sally Hopewell,et al.  Reports of clinical trials should begin and end with up-to-date systematic reviews of other relevant evidence: a status report. , 2007, Journal of the Royal Society of Medicine.

[38]  Maria J Grant,et al.  A typology of reviews: an analysis of 14 review types and associated methodologies. , 2009, Health information and libraries journal.

[39]  L. Trinquart,et al.  Commentary: Meta-epidemiology, meta-meta-epidemiology or network meta-epidemiology? , 2013, International journal of epidemiology.

[40]  Andrea Cipriani,et al.  Conceptual and Technical Challenges in Network Meta-analysis , 2013, Annals of Internal Medicine.

[41]  N. S. Hawkins,et al.  A checklist for critical appraisal of indirect comparisons , 2014, International journal of clinical practice.

[42]  Ncbi.  National Center for Biotechnology Information , 2008 .

[43]  Joseph C Cappelleri,et al.  Interpreting indirect treatment comparisons and network meta-analysis for health-care decision making: report of the ISPOR Task Force on Indirect Treatment Comparisons Good Research Practices: part 1. , 2011, Value in health : the journal of the International Society for Pharmacoeconomics and Outcomes Research.

[44]  D. Pieper,et al.  Methodological approaches in conducting overviews: current state in HTA agencies , 2014, Research synthesis methods.

[45]  Chorong Park,et al.  Methods for knowledge synthesis: an overview. , 2014, Heart & lung : the journal of critical care.

[46]  G. Guyatt,et al.  How to read a systematic review and meta-analysis and apply the results to patient care: users' guides to the medical literature. , 2014, JAMA.

[47]  Denise Thomson,et al.  The evolution of a new publication type: Steps and challenges of producing overviews of reviews , 2010, Research synthesis methods.