1. Hearing Conservation and Readiness Branch, Defense Centers for Public Health – Aberdeen , Aberdeen Proving Ground, MD 21010, USA
2. Audiology and Speech Pathology Center, Walter Reed National Military Medical Center , Bethesda, MD 20889, USA
3. Kimbrough Ambulatory Care Center , Ft. Meade, MD 20755, USA
4. Office of the Surgeon General, Defense Health Headquarters , Falls Church, VA 22042, USA