1. Veterans Affairs Palo Alto Health Care System, Palo Alto, California2Center for Health Policy and Center for Primary Care and Outcomes Research, Department of Medicine, Stanford University, Stanford, California3Stanford University School of Medicine, Stanford, California
2. Veterans Affairs Palo Alto Health Care System, Palo Alto, California3Stanford University School of Medicine, Stanford, California
3. Center for Health Policy and Center for Primary Care and Outcomes Research, Department of Medicine, Stanford University, Stanford, California3Stanford University School of Medicine, Stanford, California
4. Stanford University School of Medicine, Stanford, California4Health Research and Policy, Stanford, California