1. Department of Population Medicine Harvard Medical School & Harvard Pilgrim Health Care Institute Boston Massachusetts USA
2. Center for Pharmacoepidemiology Research and Training Center for Clinical Epidemiology and Biostatistics, and Department of Biostatistics, Epidemiology and Informatics Perelman School of Medicine University of Pennsylvania Philadelphia Pennsylvania USA
3. Endocrinology Service Department of Subspecialty Medicine Memorial Sloan Kettering Cancer Center New York New York USA