[1] Womack Army Med Ctr, Ft Bragg, NC USA
[2] Henry M Jackson Fdn Def & Vet Pain Management Ctr, Ft Bragg, NC USA
[3] Lincoln Mem Univ, Dept Math & Sci, Harrogate, TN USA
[4] Walter Reed Natl Mil Med Ctr, Bethesda, MD USA
[5] Uniformed Serv Univ Hlth Sci, Bethesda, MD 20814 USA
[6] Johns Hopkins Sch Med, Baltimore, MD USA