Textual evidence systematic reviews series paper 3: critical appraisal of evidence from narrative, opinion, and policy

JBI has long held the view that an inclusive approach to the conceptualization of what counts as evidence is important to the evidence-based movement. JBI's approach for appraising textual evidence had encompassed all forms of text (narrative, opinion, and policy), with one general tool used to guide critical appraisal. The proliferation of textual evidence and increase in textual evidence reviews demonstrate the need to reconceptualize JBI's methodological approach to critically appraising textual evidence. The objective of this paper is to outline the updated methodological approach to systematic reviews of textual evidence, especially in relation to the development of 3 separate critical appraisal tools for narrative, expert opinion, and policy text. Using an adapted Delphi approach, the JBI Textual Evidence Methodology Group convened over several rounds of meetings and discussions with international experts to reach consensus on the reconceptualization of critical appraisal tools for textual evidence sources. Strategies to effectively interrogate the legitimacy and authenticity of sources were found to be dependent upon the type of textual evidence under review. Therefore, 3 separate critical appraisal tools for narrative, expert opinion, and policy text were developed. This paper provides an overview of the development of 3 separate critical appraisal tools, highlighting the complex nature of textual evidence data sources.