What Is Real-World Data? A Review of Definitions Based on Literature and Stakeholder Interviews

Background: Despite increasing recognition of the value of real-world data (RWD), consensus on the definition of RWD is lacking. Objectives: To review definitions publicly available for RWD to shed light on similarities and differences between them. Methods: A literature review and stakeholder interviews were used to compile data from eight groups of stakeholders. Data from documents and interviews were subjected to coding analysis. Definitions identified were classified into four categories: 1) data collected in a non-randomized controlled trial setting, 2) data collected in a non-interventional/non-controlled setting, 3) data collected in a non-experimental setting, and 4) others (i.e., data that do not fit into the other three categories). The frequency of definitions identified per category was recorded. Results: Fifty-three documents and 20 interviews were assessed. Thirty-eight definitions were identified: 20 out of 38 definitions (53%) were category 1 definitions, 9 (24%) were category 2 definitions, 5 (13%) were category 3 definitions, and 4 (11%) were category 4 definitions. Differences were identified between, and within, definition categories. For example, opinions differed on the aspects of intervention with which non-interventional/non-controlled settings should abide. No definitions were provided in two interviews or identified in 33 documents. Conclusions: Most of the definitions defined RWD as data collected in a non-randomized controlled trial setting. A considerable number of definitions, however, diverged from this concept. Moreover, a significant number of authors and stakeholders did not have an official, institutional definition for RWD. Persisting variability in stakeholder definitions of RWD may lead to disparities among different stakeholders when discussing RWD use in decision making.