1. University of Iowa Hospitals and Clinics, Iowa City, Iowa (A.C.C., G.S.)
2. Long Island Jewish Medical Center, New Hyde Park, New York (C.A.B., J.W.)
3. Hennepin County Medical Center, Minneapolis, Minnesota (E.M.C., D.R.H.)
4. Coira Institute, Franklin Lakes, New Jersey (D.L.C., M.G.)
5. Columbia University Medical Center, New York, New York (P.R.M.)