The Trustees of Dartmouth College. The Dartmouth Atlas of Health Care. [Web site]. http://www.dartmouthatlas.org/ . 2014. Accessed July 25, 2014. Understanding of the Efficiency and Effectiveness of the Health Care System. For more than 20 years, the Dartmouth Atlas Project has documented glaring variations in how medical resources are distributed and used in the United States. The project uses Medicare data to provide information and analysis about national, regional, and local markets, as well as hospitals and their affiliated physicians. This research has helped policymakers, the media, health care analysts and others improve their understanding of our health care system and forms the foundation for many of the ongoing efforts to improve health and health systems across America.