New applications for individual participant data meta-analyses of randomized trials

Meta-analyses of randomized trials using individual-participant data, which represent the highest level of evidence for the evaluation of a treatment effect, are now used in different contexts in clinical research. This article aims at reviewing some of these new applications. Metaanalyses are increasingly used in economic evaluation, which implies new measure outcomes of the treatment effect, as well as in biomarkers evaluations thanks to their higher statistical power and the possibility to validate findings on independent data. This article also considers the perspectives opened up by new data sources, such as randomized trials registers, and data sharing policies.