Objective: To identify the effect that the total number of citations and team members has on the likelihood of completion and time needed for screening.

Methods: We obtained institutional review data of a large research university from Covidence. Data included review name, type, area, date created and last active, number of collaborators, presence of librarian collaboration, and the number of citations imported, screened, and removed at each step. Data were cleaned to remove items that were not true reviews and were analyzed using SPSS linear regression and independent sample Mann-Whitney U tests. Outcomes included the effect of number of total citations, number of citations per collaborator, and librarian collaboration on the percentage screened and time needed to complete title/abstract and full-text screening.

Results: The fewer citations and the fewer citations per collaborator, the more likely the team is to complete title/abstract and full-text screening, and the faster they will finish the screening process. This relationship was stronger for number of citations per collaborator than number of citations alone. There was no significant difference between the percentage screened in title/abstract for reviews with versus without librarian collaboration. However, reviews without librarian collaboration had significantly higher median percentage of full texts screened.

Conclusions: This study allows librarians to provide more informed guidance to teams on elements that may increase the likelihood of screening completion for systematic and scoping reviews. It emphasizes the importance of narrowing the scope of a review or increasing the size of the team to make screening completion more achievable.