Non-randomised evaluations of strategies to increase participant retention in randomised controlled trials: a systematic review

作者：Adel Elfeky, Katie Gillies, Heidi Gardner, Cynthia Fraser, Timothy Ishaku, Shaun Treweek · 发表于：Systematic Reviews · 年份：2020 · DOI：10.1186/s13643-020-01471-x · 被引用次数：40 · 研究领域：Ethics in Clinical Research、Meta-analysis and systematic reviews、Survey Methodology and Nonresponse

BACKGROUND: Retention of participants is essential to ensure the statistical power and internal validity of clinical trials. Poor participant retention reduces power and can bias the estimates of intervention effect. There is sparse evidence from randomised comparisons of effective strategies to retain participants in randomised trials. Currently, non-randomised evaluations of trial retention interventions embedded in host clinical trials are rejected from the Cochrane review of strategies to improve retention because it only included randomised evaluations. However, the systematic assessment of non-randomised evaluations may inform trialists' decision-making about retention methods that have been evaluated in a trial context.Therefore, we performed a systematic review to synthesise evidence from non-randomised evaluations of retention strategies in order to supplement existing randomised trial evidence. METHODS: We searched MEDLINE, EMBASE, and Cochrane CENTRAL from 2007 to October 2017. Two reviewers independently screened abstracts and full-text articles for non-randomised studies that compared two or more strategies to increase participant retention in randomised trials. The retention trials had to be nested in real 'host' trials ( including feasibility studies) but not hypothetical trials. Two investigators independently rated the risk of bias of included studies using the ROBINS-I tool and determined the certainty of evidence using GRADE (Grading of Recommendations Asse...