1 From the Department of Biomedical Informatics, Harvard Medical School (K.-H.Y., E.H., I.S.K., A.K.M.), the Department of Pathology, Brigham and Women's Hospital (K.-H.Y.), and the Harvard-MIT Division of Health Sciences and Technology (E.H.) - all in Boston; and the School of Computing, National University of Singapore, Singapore (T.-Y.L.).