1 Division of Research, Kaiser Permanente Northern California, Oakland, California.
2 Department of Health Systems Science, Kaiser Permanente Bernard J. Tyson School of Medicine, Pasadena, California; and.
3 Department of Radiology.
4 Department of Epidemiology.
5 Lineberger Comprehensive Cancer Center, and.
6 Division of Pulmonary and Critical Care Medicine, Department of Medicine, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.