1. Portia Y. Cornell ( ) is a PhD candidate in the Program in Health Policy at Harvard University, in Cambridge, Massachusetts.
2. David C. Grabowski is a professor in the Department of Health Care Policy at Harvard Medical School, in Boston, Massachusetts.
3. Marc Cohen is chief research and development officer at LifePlans Inc., in Waltham, Massachusetts.
4. Xiaomei Shi is a senior statistician at LifePlans Inc.
5. David G. Stevenson is an associate professor in the Department of Health Policy at the Vanderbilt University School of Medicine, in Nashville, Tennessee.