1 Department of Risk, Insurance and Healthcare Management, Temple University, Philadelphia, PA.
2 Division of General Medicine, University of California at Davis, Davis, CA.
3 Department of Social Medicine and Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, NC.
4 Blue Cross of California Distinguished Department of Health Policy and Management, School of Public Health and Haas School of Business, University of California, Berkeley, CA.
5 Palo Alto Medical Foundation Research Institute, Palo Alto, CA.
6 Department of Radiology, Community and Family Medicine, Dartmouth Institute for Health Policy and Clinical Practice, Lebanon, NH.