1. University of Tennessee and Veterans Affairs Medical Center, Memphis, Tennessee (R.S., M.N., B.R.B., T.M.F.)
2. Virginia Commonwealth University, Richmond, Virginia (I.S.J.)
3. Jackson Clinic and University of Tennessee, Jackson, Tennessee (A.R.)
4. University of Louisville, Louisville, Kentucky (M.P.F.)
5. Duke Clinical Research Institute, Durham, North Carolina (S.V.R.)