1. Cedars-Sinai Smidt Heart Institute, Los Angeles, California, USA
2. Center for Healthcare Value, Philip R. Lee Institute for Health Policy Studies, University of California, San Francisco, California, USA
3. Department of Epidemiology and Biostatistics and Division of Geriatrics, University of California at San Francisco and San Francisco Veterans Affairs Medical Center, San Francisco, California, USA
4. Division of General Internal Medicine, University of California, San Francisco, California, USA