Institution: | 1. Division of Biostatistics, Medical College of Wisconsin, Milwaukee, Wisconsin, U.S.A.;2. Harvard Medical School, Boston, Massachusetts, U.S.A.;3. Department of Statistics, Florida State University, Tallahassee, Florida, U.S.A.;4. Department of Biostatistics, Rollins School of Public Health, Emory University, Atlanta, Georgia, U.S.A. |