1. Charles A. Dana Research Institute, Harvard-Thorndike General Clinical Research Centre, Beth Israel Deaconess Medical Centre and Harvard Medical School, Boston, Massachusetts, Biometrics Center, Beth Israel Deaconess Medical Center, Boston, Massachusetts
2. Division of Bone and Mineral Metabolism, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, Massachusetts
3. Charles A. Dana Research Institute, Harvard-Thorndike General Clinical Research Centre, Beth Israel Deaconess Medical Centre and Harvard Medical School, Boston, Massachusetts, Divisions of Endocrinology and Metabolism and Geriatrics, Department of Medicine, University of Pittsburgh Medical Centre, Pittsburg, Pennsylvania