2,345,817
Participants
Start Date
January 31, 1994
Primary Completion Date
December 31, 2009
Study Completion Date
December 31, 2009
Group Health Cooperative, Seattle
University of North Carolina, Chapel Hill
OTHER
Dartmouth-Hitchcock Medical Center
OTHER
University of California, San Francisco
OTHER
University of Vermont
OTHER
University of New Mexico
OTHER
Kaiser Permanente
OTHER