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Source: Biometrics, Volume 67, Number 4, 1 December 2011, pp. 1406-1413(8)
Document Type: Research Article
Affiliations: 1: Departments of Epidemiology and Biostatistics, Harvard School of Public Health, 677 Huntington Avenue, Boston, Massachusetts 02115, U.S.A. 2: Department of Epidemiology, Harvard School of Public Health, 677 Huntington Avenue, Boston, Massachusetts 02115, U.S.A.
Publication date: December 1, 2011