1. Anesthesiology Department, Chronic Pain and Fatigue Research Center, University of Michigan Medical School, Ann Arbor, Michigan (K.F.B.)
2. College of Literature, Science, and the Arts, University of Michigan, Ann Arbor, Michigan (O.D.)
3. Office of the Assistant Secretary for Planning and Evaluation, U.S. Department of Health & Human Services, Washington, DC (R.L.H.)
4. Veterans Affairs Ann Arbor Healthcare System and Department of Psychiatry, University of Michigan Medical School, Ann Arbor, Michigan (A.H.).