title: Invited commentary.
authors.affiliation: Department of Anesthesiology, 4172 Cardiovascular Center, 1500 E Medical Center Dr, University of Michigan, Ann Arbor, MI48109. Electronic address: engorenm@med.umich.edu.
authors.forename: Milo
authors.initials: M
authors.lastname: Engoren
mesh_terms: D000740:Anemia / Q000150:complications*; D006348:Cardiac Surgical Procedures / Q000401:mortality*; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D008297:Male; D015233:Models, Statistical; D018570:Risk Assessment / Q000379:methods*