Leveraging observational registries to inform comparative effectiveness research.

Comparative effectiveness research (CER) has gained increased prominence over the past few years, but significant confusion surrounds the scope and definition of what constitutes CER. In some circles, CER is heralded as a tool to improve care quality and patient outcomes while simultaneously reducing health care costs. However, others contend that CER will lead to poorly designed studies whose results will be misinterpreted to limit the development and approval of new therapies. Leading to this confusion is the fact that CER spans a wide spectrum of clinical research domains that includes randomized, controlled trials; observational data analyses; and cost-effectiveness analyses. Recent federal mandates have injected significant funds for observational CER priorities, earmarked incentives for technology investments, and recommended a centralized collection of certain medical information, setting the stage for CER and observational data to gain further prominence as the foundation of many new investigations. In this review article, we define CER and highlight opportunities, and potential pitfalls, of observational registries to expand evidence through CER.