Copublication improved the dissemination of Cochrane reviews and benefited copublishing journals: a retrospective cohort study

Abstract

Objectives: To evaluate the impact of copublication on the citation of Cochrane evidence.

Study design and setting: This was a retrospective cohort study including Cochrane reviews published up to 31 December 2015 and their citing up to 11 July 2021, identified from the Web of Science Core Collection database.

Results: A total of 101 copublished and 202 noncopublished Cochrane reviews were included. The median for the total number of citations and the medians for the numbers of citations to the Cochrane review in the first, second, third, and fifth years after publication in the copublished group were higher than those in the noncopublished group [71 (interquartile range {IQR}: 37.5, 118.5) vs. 32.5 (13, 67); 1 (0, 3) vs. 0 (0, 1); 6 (3, 11.5) vs. 2 (1, 5); 8 (4, 15) vs. 3.5 (1, 8); 8 (4, 15) vs. 3 (1, 9), respectively, all P < 0.001]. Copublication of Cochrane reviews meant that 4 of 21 journals and 6 of 22 journals had a higher impact factor in the first and the second year after the copublication than they would have had without the copublication.

Conclusion: Copublication is associated with a higher citation frequency of Cochrane reviews and may increase the impact factor of the journal in which it is copublished. This facilitates broader application of Cochrane evidence and promotes its dissemination.

Keywords: Citation number; Cochrane reviews; Cohort study; Copublication; Dissemination; Journal impact factor.