1. From the VA Medical Center and University of Minnesota (I.S.A.), Minneapolis, Minn; Department of Biostatistics (L.D.F.), University of Washington, Seattle, Wash; Novartis Pharmaceuticals Corporation (Y.-T.C., R.D.G.), East Hanover, NJ; Istituto “Mario Negri” (R.L., S.M., G.T.), Milan, Italy; ANMCO Research Center (A.P.M.), Florence, Italy; and University of Minnesota (J.N.C.), Minneapolis, Minn.