O’Hare, Ann*; Johansen, Kirsten*†‡
Departments of *Medicine and †Biostatistics and Epidemiology, University of California, San Francisco, California; and ‡Department of Medicine, Veterans Affairs Medical Center, San Francisco, California.
Correspondence to Dr. Ann O’Hare, 4150 Clement St., San Francisco, CA 94121. Phone: 415-221-4810 (ext. 4953); Fax: 415-750-6949; E-mail: [email protected]
Accepted March 29, 2001
Received February 05, 2001