Lifted from www.dartmouthatlas.org :
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. Learn More
This is an awesome website that holds the data about any issue regarding health care and plans. For example, one can compare the number of heart problems in patients per state and so on. It has interactive applications built into it which can generate variety of graphs for comparisons.