1. W.B. Katzman, PT, DPTSc, OCS, Department of Physical Therapy and Rehabilitation Science, University of California, San Francisco, UCSF Box 0625, San Francisco, CA 94143-0625 (USA).
2. E. Vittinghoff, PhD, Department of Epidemiology and Biostatistics, University of California, San Francisco.
3. D.M. Kado, MD, MS, Departments of Family Medicine and Public Health and Internal Medicine, University of California, San Diego, California.
4. A.L. Schafer, MD, Department of Epidemiology and Biostatistics and Department of Medicine, University of California, San Francisco, and Medical Service, San Francisco Veterans Affairs Medical Center, San Francisco, California.
5. S.S. Wong, BS, Department of Physical Therapy and Rehabilitation Science, University of California, San Francisco.
6. A. Gladin, PT, MPT, DPT, OCS, Kaiser Permanente Northern California, San Francisco Medical Center, San Francisco, California.
7. N.E. Lane, MD, Department of Internal Medicine, University of California, Davis, Davis, California.