Simulation and matching-based approaches for indirect comparison of treatments.

Estimates of the relative effects of competing treatments are rarely available from head-to-head trials. These effects must therefore be derived from indirect comparisons of results from different studies. The feasibility of comparisons relies on the network linking treatments through common comparators; the reliability of these may also be impacted when the studies are heterogeneous or when multiple intermediate comparisons are needed to link two specific treatments of interest. Simulated treatment comparison and matching-adjusted indirect comparison have been developed to address these challenges. These focus on comparisons of outcomes for two specific treatments of interest by using patient-level data for one treatment (the index) and published results for the other treatment (the comparator) from compatible studies, taking into account possible confounding due to population differences. This paper provides an overview of how and when these approaches can be used as an alternative or to complement standard MTC approaches.