Comparative Effectiveness Research On February 17, 2009, President Obama signed into law the American Recovery and Reinvestment Act. Among its many provisions, the Act provided $1.1 billion for comparative effectiveness research (CER). The funds provided in the Act, along with the commitment to other health programs in the President’s FY10 budget present a great opportunity to improve this country’s foundation for a scientifically rigorous, twenty-first century healthcare system. In order to take full advantage of this unprecedented opportunity the following recommendations regarding the establishment of a comprehensive CER program should be considered. A comprehensive CER program should be developed to better identify the most effective health care options. Medical decisions made by patients and their providers may often be based on incomplete evidence. The goal of CER should be to provide improved clinical evidence about the use of different medical interventions for a given condition and identify the right treatment option, for the right patient, at the right time. In order to provide the best information for individual patients, CER studies should examine racial, ethnic and geographic variations in care that affect health outcomes, as well as socioeconomic factors that may limit access to or affect the type of medical care provided. A comprehensive CER program should link data from public and private entities to build upon existing data collection efforts and research capabilities. In order to create a health care system that can routinely be evaluated and improved, an advanced data infrastructure is needed. The development of a large-scale data network will require significant resources and a long term commitment from various sectors and groups. The expansion of CER activities should prioritize public-private coordination and linking of data from clinical research networks and health care databases to generate hypotheses. Although observational real-world studies have limitations and often are not appropriate for determining a course of treatment, secondary analyses of data of existing data should be used as an initial step to identify information gaps, provide transparency to research priorities, and generate hypotheses for which further clinical research may be necessary. This will help ensure that the highest priority questions are asked and that rigorous research studies are designed to further characterize variations in observed outcomes (i.e. improve understanding of identified factors that contribute to differences such as age, sex, ethnicity, comorbid conditions, etc). CER studies should support the development of personalized medicine. As scientific advances are made at an increasingly rapid rate, medicine is moving in the direction of identifying characteristics (genetic and other) that are used to guide treatment decisions toward the best outcome. Therefore, emphasis should be placed not only on the “average” patient, but on the minority who experience prolonged survival or improved quality of life who can be identified with biomarkers or other clinical characteristics. In order to continue in this necessary direction of biomedical progress, new study methods will be needed. In addition to the necessary use of randomized clinical trials, CER should seek to develop new, more efficient research techniques that can rapidly incorporate emerging scientific findings. Processes should be developed to ensure that information gained through CER is incorporated into clinical practice and better informs decisions made among patients, their health care providers, and payers. Independent and transparent CER studies should be used to improve medical decision making. While costs should be communicated, a comprehensive CER program should evaluate clinical outcomes first, rather than to seek to limit the use of health interventions on the basis of their costs alone. Best practices of communicating the results of CER should be identified and should add to the body of evidence routinely created through real-world practice and collected through scientifically rigorous processes, such as medical professional societies. Generating and using additional information on comparative effectiveness will lead to improved decisions by patients, physicians, health care purchasers, and others, thereby improving overall health care for decades to come.