Methodological quality of umbrella reviews in endodontics: A cross-sectional study

Introduction: In endodontics, the number of umbrella reviews has increased significantly over the last few years, but there is no evidence that they were methodologically sound. The aim of the current study was to appraise the methodological quality of umbrella reviews in endodontics, and to identify possible predictive factors associated with methodological quality. Methods: Umbrella reviews published in the discipline of endodontics until December 2023 were included. The methodological quality of the reviews was evaluated using a checklist consisting of 11 items. Each item in the checklist was evaluated by two independent assessors who assigned a score of ‘1’ if it was fully addressed, ‘0.5’ if it was partially ddressed, and ‘0’ if it was not addressed. Bootstrapped multiple linear regression analysis was used to examine the association between the total scores awarded and five predictor variables (a priori protocol registration, year of publication, number of authors, journal impact factor (IF) and continent of the corresponding author). The statistical significance level was set as 5%. Results: A total of 27 reviews were included. Ninety-six per cent of the reviews adequately reported: eligibility criteria for selecting the reviews, details of the reviews, techniques for assessing the risk of bias or methodological quality of the individual systematic reviews they included. Only 30% of the reviews adequately managed overlapping primary studies within individual systematic reviews. Among the five predictors analysed, a priori protocol registration and journals with IFs were associated with significantly greater total methodological quality scores. Discussion: Several methodological shortcomings in the umbrella reviews published within the field of endodontics were revealed. Umbrella reviews published in journals with IFs and those with protocols registered a priori had significantly superior methodological quality scores. Conclusion: In endodontics, authors intending to publish umbrella reviews should consider the limitations revealed in this study and follow the appropriate rules to ensure their reviews comply with the highest standards and provide accurate and dependable information and conclusions.