real world evidence (rwe) in medicine means evidence obtained from real world data (rwd), which are observational data obtained outside the context of randomized controlled trials (rcts) and generated during routine clinical practice. in order to assess patient outcomes and to ensure that patients get treatment that is right for them, real world data needs to be utilized. rwe is generated by analyzing data which is stored in electronic health records (ehr), medical claims or billing activities databases, registries, patient-generated data, mobile devices, etc. it may be derived from retrospective or prospective observational studies and observational registries. in the usa the 21st century cures act required the fda to expand the role of real world evidence.