1. Kaiser Permanente Division of Research , 2000 Broadway, Oakland, CA 94612 , USA
2. Kaiser Permanente Santa Clara Medical Center , 700 Lawrence Expy, Santa Clara, CA 95051 , USA
3. Department of Radiological Sciences, University of California Irvine School of Medicine , 1001 Health Sciences Rd, Irvine, CA 92617 , USA
4. Medical Measurement Team, Korea Research Institute of Standards and Science , 267 Gajeong-ro, Yuseong-gu, Daejeon 34113 , South Korea
5. Departments of Epidemiology, Biostatistics and Medicine, University of California at San Francisco , 505 Parnassus Ave, San Francisco, CA 94143 , USA