Reassessing the Role of Google Scholar in PRISMA-Informed Systematic Reviews Through a Critical Analysis of Influential Research Identifying Its Limitations and Empirical Evidence

There is contested use of Google Scholar as a primary database for PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) reviews. However, well-cited articles identify Google Scholar as insufficiently reliable and evaluate its use as supplementary. Subsequent systematic review searches have accepted this relegation of Google Scholar to supplementary status, citing these articles as the reason. This study questions this acceptance by (1) revealing the type of difficulties with Google Scholar identified in these well-cited publications compared with PRISMA guidelines, and (2) examining several PRISMA scoping review primary database searches performed by this author since 2023 for the adequacy of Google Scholar results compared with them. The results reveal that the reasons for considering Google Scholar a supplementary database regarding PRISMA status are not convincing, as they are unrelated to PRISMA guidelines for systematic reviews. Google Scholar returned the greatest number of included studies for the majority of post-2023 scoping reviews conducted by this author. These results demonstrate that the accepted advice to authors that Google Scholar should be a supplementary database is unsupported. Based on the results of this research, the suggestion is to accept Google Scholar as a primary database, comparable in all relevant ways to other primary databases for a PRISMA-style review.