[1] HARVARD UNIV,DEPT PREVENT & SOCIAL MED,CAMBRIDGE,MA 02115
[2] NEI,OFF BIOMETRY & EPIDEMIOL,BETHESDA,MD 20014
[3] UNIV ARIZONA,DEPT OPHTHALMOL,TUCSON,AZ 85721
[4] BOSTON UNIV,DEPT OPHTHALMOL,BOSTON,MA 02215
[5] BOSTON UNIV,DEPT MED,BOSTON,MA 02215