1. From the Departments of Radiology and Biomedical Imaging (A.M., X.W., H.P.F., C.C.M.), Economics (H.P.F.), Management (H.P.F.), Public Health (H.P.F.), and Neurosurgery (C.C.M.), Yale School of Medicine, 333 Cedar St, Box 208042, Tompkins East 2, New Haven, CT 06520-8042; Harvey L. Neiman Health Policy Institute, Reston, VA (D.R.H.); Department of Radiology, University of Maryland School of Medicine, Baltimore, MD (D.G.); and Department of Radiology, Northwell Health, Manhasset, NY (P.S.).