1. From the Clinical Epidemiology Unit, Department of Community Health Sciences (T.H.J., J.H.), the Section of Nephrology, Department of Medicine (T.H.J.), and the Department of Medicine (M.I.), Aga Khan University, Karachi, Pakistan; the Division of Nephrology (T.H.J., A.S.L.) and the Division of Clinical Care Research (C.H.S.), Tufts-New England Medical Center, Department of Medicine, Tufts University School of Medicine School, Boston, Mass; and the National Heart and Lung Institute, Imperial College...