Methodological advances in evidence synthesis
JBI Evidence Synthesis special issue released
JBI Evidence Synthesis has released a special issue coinciding with JBI Methodology Month, which marks its fourth year in 2025.
Held every March, JBI Methodology Month aims to advance the quality of evidence syntheses and underscores the importance of reliable evidence to inform healthcare policy and practice. Designed for authors, students, healthcare professionals, and peer reviewers, Methodology Month also highlights the need to adhere to rigorous methodologies for diverse types of evidence synthesis.
The special issue of JBI Evidence Synthesis, Volume 23, Issue 3 for March 2025, presents a variety of articles related to the methodological conduct of evidence synthesis. ?
A key feature of this special issue is the first in a series of three papers from the JBI Textual Evidence Methodology Group outlining updates to JBI's methodological approach to systematic reviews of textual evidence. The paper provides an introduction to the revised JBI methodology and overview of recent changes. This paper is the first of a series and presents a re-conceptualisation of JBI’s approach to the synthesis of textual evidence, drawing upon discourse analysis. It provides an overview of changes as they relate to how this evidence type is defined, clarifies terminology, and offers guidance on when a review of this nature should be conducted.
JBI recognises that diverse questions require diverse types of evidence, and textual evidence systematic reviews serve as a vital link when empirical data is absent, insufficient, or inadequately contextualised. This revised methodology builds upon JBI's long-standing view that an inclusive approach to evidence is important, acknowledging the value of narrative accounts, expert opinions, and policy documents in informing decisions. The series will further explore challenges in developing search strategies for textual evidence and improvements to critical appraisal tools for narrative, expert opinion, and policy in subsequent papers.
Another significant contribution to JBI methodology highlighted in this issue is the paper titled Methods for data extraction and data transformation in convergent integrated mixed methods systematic reviews. This article, authored by Lizarondo et al., expands on the current guidance for JBI convergent integrated mixed methods systematic reviews by describing data transformation involving qualitisation. The paper distinguishes data extraction from qualitisation, with qualitisation occurring after the extraction process as part of the integration process. This methodological investigation addresses the diverse understandings of data transformation within mixed methods systematic reviews and aims to provide a more comprehensive methodology for data extraction and transformation via qualitisation.
The special issue also features the introduction of the revised JBI critical appraisal tool for the assessment of the risk of bias for cohort studies. ?Authored by Barker et al., this revision aims to reflect recent advancements in methodological research and improve the tool's relevance and longevity. The updated critical appraisal tool also aims to be compatible with the reporting requirements established by PRISMA 2020 and the methodological requirements of the GRADE approach when assessing certainty in the evidence. This revision is part of a larger effort by the JBI Effectiveness Methodology Group to update the entire suite of JBI critical appraisal tools for quantitative study designs to better align with recent advancements in risk-of-bias science.
Finally, the issue includes a scoping review that examined the application of JBI guidance in published qualitative systematic reviews from 2022. This review, Addressing equity, diversity, and inclusion in JBI qualitative systematic reviews: a methodological scoping review conducted by Evans et al., aimed to map and summarise key features of a sample of evidence to understand how health equity was (or was not) addressed in these reviews. The findings provide insights into the current practices in conducting JBI qualitative systematic reviews and highlight areas for potential improvement in addressing equity, diversity, and inclusion. The review notes the emphasis of the JBI ConQual approach on the methodological quality of underpinning studies when considering confidence in synthesised findings.
This special issue of JBI Evidence Synthesis for Methodology Month 2025 offers important methodological advancements and guidance for researchers and practitioners involved in evidence synthesis, reinforcing JBI's commitment to promoting rigorous and reliable evidence-based healthcare. The diverse range of articles underscores the ongoing evolution of evidence synthesis methodologies to address complex research questions and inform decision-making effectively. Methodological guidance for 8 different types of evidence syntheses is available in the JBI Manual for Evidence Synthesis.
To follow JBI Methodology Month across social media, use the hashtag: #JBImethodology
The special issue also includes articles:
Abdulmajeed, Jazeel; Furuya-Kanamori, Luis; Chivese, Tawanda; Xu, Chang; Thalib, Lukman; Doi, Suhail A.R. ?
JBI Evidence Synthesis.?23(3):480-492, March 2025.
Whitehorn, Ashley; Lockwood, Craig; Hu, Yan; Xing, Weijie; Zhu, Zheng; Porritt, Kylie ?
JBI Evidence Synthesis.?23(3):493-516, March 2025