1. M.R. Scherer, PT, MPT, NCS, is CPT, US Army, Army Medical Specialist Corps, and a PhD student in the Department of Physical Therapy and Rehabilitation Science, University of Maryland School of Medicine, 100 Penn St, Baltimore, MD 21201 (USA).
2. M.C. Schubert, PT, PhD, is Assistant Professor, Department of Otolaryngology–Head and Neck Surgery, Johns Hopkins School of Medicine, Baltimore, Maryland.