Meta-Analysis for Time-to-event Outcome Based on Restored Individual Participant Data and Summary Statistics

Abstract

In meta-analyses, Individual Participant Data (IPD) is considered the gold standard for summarizing results from individual studies. However, in studies focusing on survival outcomes, the IPD is often unavailable, and researchers typically present Kaplan-Meier curves alongside summary statistics like hazard ratios. Recently, methods have been developed to reconstruct IPD from Kaplan-Meier curves, enabling meta-analyses without relying on summary statistics alone. Nonetheless, the accuracy of meta-analyses based on reconstructed IPD compared to those using true IPD has not been well-examined. This paper assesses the utility of reconstructed IPD in meta-analyses through simulation studies and real-data re-analysis. Our findings suggest that meta-analyses using reconstructed IPD yield results comparable to those obtained with true IPD, provided that a sufficient number of data points are available from the Kaplan-Meier curves for IPD reconstruction. Therefore, meta-analyses based on reconstructed IPD can offer sufficient precision when true IPD is unavailable, presenting a viable alternative approach.