An Overview of Retraction Status and Reasons of Non-Cochrane Systematic Reviews in Medicine

BackgroundMany previous studies have analyzed the status of retracted publications from different perspectives, but so far no study has focused on systematic reviews (SRs). The purpose of this study is to analyze the retraction status and reasons of non-Cochrane SRs in the field of medicine. MethodsWe searched MEDLINE and Embase from their inception to April 18, 2020, as well as Retraction Watch Database and Google Scholar with no language restriction to find non-Cochrane SRs that were retracted for any reason. Two reviewers independently screened and extracted data. We describe the characteristic and reasons of retraction and the duration from publication to retraction. ResultsWe identified 150 non-Cochrane SRs in medicine retracted between 2004 and 2020. The majority of retracted SRs were led by authors from China and affiliated with hospitals. Most SRs were published in journals with an impact factor [≤]3, and in journal ranked in the third quarter. The largest proportion of retraction notices were issued by the publisher and editor(s) jointly; seven did not report this information. Fraudulent peer-review was the most common reason for retraction, followed by unreliable data meaning errors in study selection or data analysis. The median time between publication and retraction was 14.0 months. SRs retracted due to research misconduct took longer to retract than SRs retracted because of honest error. ConclusionsThe situation with retracted SRs is critical globally, and in particular in China. The most common reasons for retraction are fraudulent peer-review and unreliable data, and in most cases the study is retracted more than a year after publication. Efforts should be made to improve the process of peer review and adherence to the COPE retraction guidance, while at the same time authors should strengthen their skills in SR methodology.