From the Department of Mathematics and Statistics, Boston University, Boston, Massachusetts (P.K.E., M.F.E., R.B.D.); the Department of Biostatistics, Boston University School of Public Health, Boston, Massachusetts (L.M.S.); and the Department of Neurology, Boston University School of Medicine, Boston, Massachusetts (P.A.W.).
Address correspondence and reprint requests to Penelope K. Elias, PhD, Statistics and Consulting Unit, Department of Mathematics and Statistics, Boston University, 111 Cummington St., Boston, MA 02215. E-mail: [email protected]
Received for publication December 16, 2002; revision received August 17, 2004.
This research was supported by NHLBI’s Framingham Heart Study (NHLBI/NIH Contract # N01–25195), and Grants: NIA 5R01-AG 16495, NIA 5R01-AG08122, NIA 4RO1 HL65177, NINDS 5R01-NS17950, Boston University ADC P30 AG13846 and NHLBI 3RO1 HL67358.