Update on Data Reuse in Health Care.

Objective: Reuse of clinical data has broad use in clinical, research, governmental, and business settings. This summary provides an update on the benefits, barriers to use with large clinical databases, policy frameworks that have been formulated, and challenges. Methods: This report highlights some recent publications on the diverse uses of clinical data and some policy initiatives to promote reuse. It also contains the opinions of the author. Results: Although many examples of the benefits of data reuse have been documented, this summary also reviews why the quality of clinical data needs to be the focus of future informatics work. Conclusion: The promise of reusing data outweighs potential risks, but concerns about privacy and the need to modernize our legal framework will be necessary to realize the full benefits of real-world evidence.