Meta-epidemiological review identified variable reporting and handling of time-to-event analyses in publications of trials included in meta-analyses of systematic reviews

Objectives: Previous findings indicate limited reporting of systematic reviews with meta-analyses of time-to-event (TTE) outcomes. We assessed corresponding available information in trial publications included in such meta-analyses.Study Design and Setting: We extracted data from all randomized trials in pairwise, hazard ratio (HR)-based meta-analyses of pri-mary outcomes and overall survival of 50 systematic reviews systematically identified from the Cochrane Database and Core Clinical Jour-nals. Data on methods and characteristics relevant for TTE analysis of reviews, trials, and outcomes were extracted.Results: Meta-analyses included 235 trials with 315 trial analyses. Most prominently assessed was overall survival (91%). Definitions (61%), censoring reasons (41%), and follow-up specifications (56%) for trial outcomes were often missing. Available TTE data per trial were most frequently survival curves (83%), log-rank P values (76%), and HRs (72%). When trial TTE data recalculation was reported, reviews mostly specified HRs or P values (each 5%). Reviews primarily included intention-to-treat analyses (64%) and analyses not adjusted for covariates (25%). Except for missing outcome data, TTE-relevant trial characteristics, for example, informative censoring, treatment switching, and proportional hazards, were sporadically addressed in trial publications. Reporting limitations in trial publications translate to the review level.Conclusion: TTE (meta)-analyses, in trial and review publications, need clear reporting standards.& COPY; 2023 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

This study assessed the reporting of time-to-event (TTE) outcomes in clinical trial publications included in meta-analyses. Data were extracted from 50 systematic reviews identified from the Cochrane Database and Core Clinical Journals, including information on trial methods, characteristics, and TTE analysis. The study found that there were often missing information on definitions, censoring reasons, and follow-up specifications in trial publications. Commonly reported TTE data in trials included survival curves, log-rank P values, and hazard ratios (HRs). Reviews mostly specified HRs or P values when recalculating trial TTE data. The reporting limitations in trial publications translated to the review level.