Understanding the Influence of Predatory Journals Articles Included within Systematic Reviews: A Scoping Review

Predatory journals are characterized by their emphasis on selfinterest over academic integrity. Research on these journals predominantly aims at their identification to mitigate their influence. Yet, the exploration of how articles from predatory journals affect systematic reviews remains limited. The primary objective of this study is to understand the extent of our current knowledge on how predatory publishing impacts evidence syntheses. The secondary objective is to collect and implement a set of strategies to minimize the inclusion of predatory journals. A systematic search was performed in the PubMed, Scopus, and Embase databases on April 7^th, 2024, in line with PRISMA methodology. Only studies exploring how predatory publishing affects systematic reviews were included. A total of 7 articles were included. One found that 157 systematic reviews cited at least one article from predatory journals. Another discovered that nine percent of trials in a large Cochrane review were from presumed predatory publications. A third study found that, out of 6,750 citations in 300 reviews, 55 were presumably from predatory journals. Different strategies were discussed, such as tools to assess quality and common indicators of predatory articles, information on indexing and its significance, and a team based approach with experts in the field to establish correct research protocols. Our scoping review highlights the significant issue of predatory journals being included in systematic reviews and calls for more bibliometric quantitative analysis. It also discusses strategies to prevent the inclusion of low quality research in evidence syntheses, particularly useful for early career researchers.