Note: Relevant resources related to the listed knowledge synthesis methods are provided below as full citations and/or URLs. Some of the URL links may change over time as resources are continuously updated; the links were last accessed in April 2022.
Description
A form of knowledge synthesis that addresses an exploratory research question aimed at mapping key concepts, types of evidence, and gaps in research related to a defined area or field by systematically searching, selecting, and synthesizing existing knowledge.1
A form of knowledge synthesis that attempts to collate all empirical evidence that fits pre-specified eligibility criteria in order to answer a specific research question. Systematic reviews use explicit, systematic methods that are selected with a view to minimize bias, thus providing more reliable findings from which conclusions can be drawn and decisions made. 2
In the context of a systematic review, a network meta-analysis is a meta-analysis in which multiple treatments (that is, three or more) are being compared using both direct comparisons of interventions within randomized controlled trials and indirect comparisons across trials based on a common comparator.4
A form of knowledge synthesis that utilized prevalence and incidence data to describe geographical distribution of a disease or health condition and the variation in the distribution between subgroups (e.g. gender or socioeconomic status). Synthesizing such data is necessary to monitor trends in disease burden and emergence and to contribute to the design of further etiological studies. 5
A form of knowledge synthesis that are systematic reviews of reviews and seek to provide an overview on a topic, rather than focus on a single intervention. They summarize the evidence across the plethora of intervention providers, settings, type, quality and time. The primary differences between reviews on the same topic can also be explained within an overview. 6, 7
A form of knowledge synthesis that summarizes and analyzes evidence from prognostic studies in a systematic review and meta-analysis. Prognosis studies seek to understand average (overall) prognosis, prognostic factors, risk prediction models, and treatment effect modification.9
A form of knowledge synthesis that summarizes the evidence on the accuracy (e.g. sensitivity, specificity, likelihood ratios) of a test or instrument.10
A form of knowledge synthesis that searches, identifies and synthesizes data from burden of illness studies or monetary cost studies. Given the disparity in methods used across such studies, the challenge lies in synthesizing the data into a coherent whole.11
A form of knowledge synthesis that searches, identifies and synthesizes data from economic evaluation studies. This type of systematic review seeks to help decision makers understand the resource allocation problem and the potential impact of the added cost to obtain a unit of effectiveness (e.g., the cost of gaining one quality-adjusted life year). Such reviews should focus less on trying to generate a summarized estimate of the cost-effectiveness ratio and more on demonstrating the extent to which this ratio varies from setting to setting, and why.12
A form of knowledge synthesis in which components of the systematic review process are simplified or omitted to produce information in a timely manner.13, 14
Higgins JPT, Green S (editors). Cochrane Handbook for Systematic Reviews of Interventions
Version 5.1.0 [updated March 2011]. The Cochrane Collaboration, 2011. Available from:
www.handbook.cochrane.org
Deeks JJ, Higgins JPT, Altman DG (editors). Chapter 10: Analysing data and undertaking metaanalysis. In: Higgens JPT, Thomas J, Chandler J, Cumpston M, Li T, Page MJ, Welch VA (editors). Cochrane
Handbook for Systematic Reviews of Interventions version 6.0 [updated July 2019]. Cochrane, 2011.
Available from: www.handbook.cochrane.org
Chaimani A, Caldwell DM, Li T, Higgins JPT, Salanti G. Chapter 11: Undertaking network metaanalyses. In: Higgens JPT, Thomas J, Chandler J, Cumpston M, Li T, Page MJ, Welch VA (editors).
Cochrane Handbook for Systematic Reviews of Interventions version 6.0 [updated July 2019]. Cochrane,
2019. Available from: www.handbook.cochrane.org
Munn Z, Moola S, Lisy K, Riitano D, Tufanaru C. Chapter 5: Systematic reviews of prevalence and incidence. In: Aromataris E, Munn Z (Editors). Joanna Briggs Institute Reviewer's Manual. The Joanna
Briggs Institute, 2017. Available from: https://reviewersmanual.joannabriggs.org/
Aromataris E, Munn Z (Editors). Joanna Briggs Institute Reviewer's Manual. The Joanna Briggs
Institute, 2017. Available from https://reviewersmanual.joannabriggs.org/
Baker PR, Costello JT, Dobbins M, Waters EB. The benefits and challenges of conducting an
overview of systematic reviews in public health: a focus on physical activity. Journal of public health.
2014;36(3):517-21.
Pai M, McCulloch M, Enanoria W, Colford JM, Jr. Systematic reviews of diagnostic test
evaluations: What's behind the scenes? ACP journal club. 2004;141(1):A11-3.
Gomersall JS, Jadotte YT, Xue Y, Lockwood S, Riddle D, Preda A. The Joanna Briggs Institute
Reviewer's Manual 2014: The Systematic Review of Economic Evaluation Evidence. The Joanna Briggs
Institute, 2014. Available from: https://nursing.lsuhsc.edu/JBI/docs/ReviewersManuals/Economic.pdf.
Shemilt I, Aluko P, Graybill E, Craig D, Henderson C, Drummond M, et al.; on behalf of the
Campbell and Cochrane Economics Methods Group. Chapter 20: Economic evidence. In: Higgens JPT,
Thomas J, Chandler J, Cumpston M, Li T, Page MJ, Welch VA (editors). Cochrane Handbook for
Systematic Reviews of Interventions version 6.0 [updated July 2019]. Cochrane, 2011. Available from:
www.handbook.cochrane.org
Khangura S, Konnyu K, Cushman R, Grimshaw J, Moher D. Evidence summaries: the evolution of a rapid review approach. Syst Rev. 2012;1:10.
Concept analysis, whether theoretical or colloquial, articulates concepts that already have a home in some domain: in scientific theories, among people in a community or both. Concept analysis is thus merely a phase of the concept development process. It makes existing concepts explicit objects of reflection and this is especially important where theories are being borrowed and modified. Methods of concept analysis are an important part of theory development. Theorists have adopted methods of concept analysis from philosophy and conceptual meaning depends on the context of use. Concepts are developed by testing and modifying the theories of which they are a part. Theoretical concept analysis and colloquial concept analysis have different purposes and evidence bases. When using a concept analysis, researchers should attend carefully to the evidence base of the analysis.1
Key Methodological Paper Describing Method [Relevant Sections]
Framework synthesis promotes generalization of findings through use of theory. Specifically, a theoretical framework will enable systematic identification and understanding of drivers that predict success in different settings, guide adaption of targeted practice changes and implementation strategies, and more quickly and confidently build the scientific knowledge base. Framework synthesis derives its main operating principles from framework analysis of primary data. Framework analysis is best adapted to research with specific questions, a limited timeframe and issues that have been identified a priori. Although framework analysis may generate theories, the prime concern is to describe and interpret what is happening in a particular setting. Framework synthesis offers a flexible vehicle for analysis and synthesis of secondary data; analysis and synthesis of primary data; integration of primary data with secondary data; and integration of quantitative and qualitative data, of either primary or secondary origin.2
Key Methodological Paper Describing Method [Relevant Sections]
Meta-aggregation is philosophically grounded in pragmatism and transcendental phenomenology. The essential characteristics of a meta-aggregative review are that the reviewer avoids re-interpretation of included studies, but instead accurately and reliably presents the findings of the included studies as intended by the original authors.3
Key Methodological Paper Describing Method [Relevant Sections]
Technique to synthesize qualitative research or develop ‘‘translations of qualitative studies into one another’’ (i.e., reciprocal translation analysis). Interpretive approach that aims to provide a new interpretation of these studies or a new theory to explain the range of research findings encountered, rather than a simple aggregation. A way of reanalyzing and comparing the texts of published studies (rather than the original data of each) to produce a new interpretation. Involves induction and interpretation, whereby separate parts are brought together to form a ‘‘whole’’ (i.e., looking for a new theory or ‘‘line of argument’’ to explain all the studies) so that the result is greater than the sum of its parts. 4
Key Methodological Paper Describing Method [Relevant Sections]
Term used to describe theoretical synthesis methods that provide a broader understanding of human behavior and experience and should lead to new insights that are not observed in the original studies. Specifically, it is an iterative process that uses interpretation of interpretations and theoretical sampling of studies for synthesis until theoretical saturation is reached. 4
Key Methodological Paper Describing Method [Relevant Sections]
A multifaceted, interpretive approach to synthesis developed to study the experiences of patients living with chronic illness. Consists of three components to be completed before synthesis: meta-data analysis, meta-method, and meta-theory. Collectively, these create a new interpretation accounting for the results of all three elements of analysis (called meta-synthesis). 5
Key Methodological Paper Describing Method [Relevant Sections]
A quantitatively oriented summary of qualitative findings developed to accommodate the distinctive features of qualitative surveys. Can be used to combine descriptive quantitative and qualitative studies. The approach includes the extraction, grouping and formatting of findings, and the calculation of frequency and intensity effect sizes, which can be used to produce mixed research syntheses and to conduct analyses of the relationship between reports and findings. May be used to develop a map of qualitative studies, which can serve as a basis for a further synthesis. 5
Key Methodological Paper Describing Method [Relevant Sections]
In a systematic review, narrative summary typically involves the selection, chronicling, and ordering of evidence to produce an account of the evidence.4 Its form may vary from the simple recounting and description of findings through to more interpretive and explicitly reflexive accounts that include commentary and higher levels of abstraction. Narratives of the latter type can account for complex dynamic processes, offering explanations that emphasize the sequential and contingent character of phenomena. 6
Key Methodological Paper Describing Method [Relevant Sections]
Draws out central theories or causal mechanisms identified in multiple studies and builds an explanation of the body of research by telling the story of the evolution of the field or mapping the domains covered by the literature in an area. Created using the methods of thematic analysis, conceptual mapping, and critical reflection on the synthesis process. Process of compiling descriptive data and exemplars from individual studies and building them into a mosaic or map (i.e., meta-narrative mapping). 6
Key Methodological Paper Describing Method [Relevant Sections]
This is a social work specific name for qualitative evidence synthesis. Qualitative evidence synthesis in the context of Cochrane systematic reviews explores the meanings that people attach to phenomena, using people's experiences of conditions, of receiving interventions or delivering interventions to help explain, interpret, and apply the results of an intervention review. 7
Key Methodological Paper Describing Method [Relevant Sections]
Thematic synthesis applies thematic analysis to study data in a systematic review of multiple qualitative studies. Thematic analysis is a method that is often used to analyse data in primary qualitative research. Thematic synthesis has three stages: the coding of text 'line-by-line', the development of 'descriptive themes', and the generation of 'analytical themes'. While the development of descriptive themes remains 'close' to the primary studies, the analytical themes represent a stage of interpretation whereby the reviewers 'go beyond' the primary studies and generate new interpretive constructs, explanations or hypotheses. 8
Key Methodological Paper Describing Method [Relevant Sections]
There is currently no methodological guidance to direct the conduct of rapid qualitative evidence synthesis. 9 Examples of rapid qualitative evidence syntheses are available that use different approaches to expedite the completion of these reviews. 9 These approaches largely mirror those developed for rapid reviews of interventions.10
Key Methodological Paper Describing Method [Relevant Sections]
Risjord M. Rethinking concept analysis. J Adv Nurs. 2009;65(3):684-91.
Booth A, Carroll C. How to build up the actionable knowledge base: the role of 'best fit'
framework synthesis for studies of improvement in healthcare. BMJ Qual Saf. 2015;24(11):700-8.
Lockwood C, Munn Z, Porritt K. Qualitative research synthesis: methodological guidance for
systematic reviewers utilizing meta-aggregation. Int J Evid Based Healthc. 2015;13(3):179-87.
Tricco AC, Antony J, Soobiah C, Kastner M, Cogo E, MacDonald H, et al. Knowledge synthesis
methods for generating or refining theory: a scoping review reveals that little guidance is available. J Clin
Epidemiol. 2016;73:36-42.
Tricco AC, Antony J, Soobiah C, Kastner M, MacDonald H, Cogo E, et al. Knowledge synthesis
methods for integrating qualitative and quantitative data: a scoping review reveals poor
operationalization of the methodological steps. J Clin Epidemiol. 2016;73:29-35.
Dixon-Woods M, Agarwal S, Jones D, Young B, Sutton A. Synthesising qualitative and
quantitative evidence: a review of possible methods. J Health Serv Res Policy. 2005;10(1):45-53.
Harris JL, Booth A, Cargo M, Hannes K, Harden A, Flemming K, et al. Cochrane Qualitative and
Implementation Methods Group guidance series-paper 2: methods for question formulation, searching,
and protocol development for qualitative evidence synthesis. J Clin Epidemiol. 2018;97:39-48.
Thomas J, Harden A. Methods for the thematic synthesis of qualitative research in systematic
reviews. BMC Med Res Methodol. 2008;8:45.
Campbell F, Weeks L, Booth A, Kaunelis D, Smith A. A scoping review found increasing examples
of rapid qualitative evidence syntheses and no methodological guidance. J Clin Epidemiol. 2019;115:160-
71.