Real-world evidence. Benefits and limitations in multiple sclerosis research

Real-world evidence (RWE) expands the data obtained in randomized clinical trials (RCTs), which are based on both homogeneous selected patient groups and limited study durations, to long-term experiences in clinical routine. In particular, chronic diseases such as multiple sclerosis (MS) with both heterogeneous pathologies and a growing number of therapeutic options require a careful RWE-based assessment of long-term efficacy and safety parameters. This review presents RWE data sources applied in MS research and discusses potential quality standards. This article is based on the results of an expert meeting of the authors held in October 2015 and a selective literature search. The RWE data sources include the reporting system of drug safety monitoring, non-interventional studies, MS-specific registries, administrative health databases, and electronic medical records. These data sources have different objectives and are subject to specific limitations with respect to the disease and therapy-relevant analytical options. The combination of different sources into an integrative approach might improve the validity of RWE in MS research; however, this objective requires the standardization of data collection and processing as well as the definition of uniform and transnational quality standards. There is still a need for high-quality, comprehensive, and valid RWE data as these data cover additional aspects of patient care and expand the data available by complementary information. Further development of an integrative RWE approach requires cooperation at various levels with the aim of the best possible standardization and harmonization of clinical MS data.