1 Department of Cardiology, Tufts University Medical Center, Boston, Massachusetts, USA.
2 Department of Research and Evaluation, Kaiser Permanente, Southern California, Pasadena, California, USA.
3 Department of Cardiology, Kaiser Permanente Los Angeles Medical Center, Los Angeles, California, USA.
4 Department of Cardiology, Kaiser Permanente Oakland Medical Center, Oakland, California, USA; Division of Research, Kaiser Permanente Northern California, Pleasanton, California, USA.
5 Department of Research and Evaluation, Kaiser Permanente, Southern California, Pasadena, California, USA. Electronic address: Wansu.Chen@kp.org.