Expressions of concern (EoC) can reduce the adverse effects of unreliable publications by alerting readers to concerns about publication integrity while assessment is undertaken. We investigated the use of EoC for 463 publications by two research groups for which we notified concerns about publication integrity to 142 journals and 44 publishers between March 2013 and February 2020. By December 2021, 95 papers had had an EoC, and 83 were retracted without an EoC. Median times from notification of concerns to EoC (10.4mo) or retraction without EoC (13.1mo) were similar. Among the 95 EoCs, 29 (30.5%) were followed by retraction after a median of 5.4mo, none was lifted, and 66 (69.5%) remained in place after a median of 18.1mo. Publishers with >10 notified publications issued EoCs for 0-81.8% of papers: for several publishers the proportions of notified papers for which EoCs were issued varied considerably between the 2 research groups. EoCs were issued for >30% of notified publications of randomized clinical trials and letters to the editor, and <20% of other types of research. These results demonstrate inconsistent application of EoCs between and within publishers, and prolonged times to issue and resolve EoCs.
Keywords: Committee on Publication Ethics; Publication Ethics; Publication integrity; academic publishing; expression of concern; research integrity; retraction.