1. University of Michigan Medical School and Veterans Affairs Ann Arbor Healthcare System, Ann Arbor, Michigan (P.K.P., M.T.G., S.S., V.C.)
2. University of Michigan Medical School, Ann Arbor, Michigan (K.J., A.S.)
3. Health Research & Educational Trust, American Hospital Association, Chicago, Illinois (A.J.R.)
4. Center for Clinical Management Research, Veterans Affairs Ann Arbor Healthcare System, Ann Arbor, Michigan (D.R.)