Contemporary practices in scoping review protocol registration: a meta-research analysis of high-impact health journals (2024–2025)

BACKGROUND: Scoping reviews are widely used across the health sciences to map evidence, clarify concepts, and identify knowledge gaps. Although protocol development and registration are increasingly encouraged, empirical evidence describing contemporary registration practices remains limited. METHODS: This study aimed to evaluate current practices in scoping review protocol registration and reporting in high-impact health sciences journals published between 2024 and 2025. We conducted an empirical meta-research study of scoping reviews published in first-quartile journals according to the Journal Citation Reports and indexed in PubMed. Data were extracted independently using a standardized form and included protocol registration status, registry platform, public accessibility, peer-reviewed protocol publication, reported protocol components, and methodological guidance cited. Descriptive analyses were used to assess registration patterns and methodological consistency. Multivariable logistic regression models were fitted to explore factors associated with protocol registration reporting and the presence of a peer-reviewed protocol. RESULTS: Among 2,546 screened records, 1,267 scoping reviews underwent full data extraction. Overall, 549 reviews reported a registered protocol, of which 483 were publicly accessible and included in the analysis. Protocol registration was identified in 43.3% of scoping reviews, while peer-reviewed protocol publication was rare (5.1%). Most protocols were registered on the Open Science Framework (OSF) (n = 478). Protocol content frequently included core methodological elements but also reported additional items beyond those addressed in the JBI Manual for Evidence Synthesis. Although many methodological documents were cited, only two provided explicit guidance for scoping review protocol development. Post hoc analyses identified substantial heterogeneity in protocol registration practices across journals, publishers, and corresponding author countries, suggesting that registration practices are influenced by a combination of editorial policies, local research cultures, and differing methodological perspectives. CONCLUSION: Protocol registration practices in scoping reviews remain heterogeneous across high-impact health sciences journals. The findings demonstrate substantial variability in protocol content, registration approaches, and use of methodological guidance, while reinforcing ongoing methodological discussions regarding protocol registration and standardization in scoping reviews.