Agrawal, Y, Carey, JP, Hoffman, HJ, Sklare, DA, and Schubert, MC. The modified Romberg balance test: Normative data in US adults. Otology & Neurotology: 2011; 32(8):1309-1311. For the National Health and Nutrition Examination Survey (NHANES) Balance Exam Procedures Manual see http://www.cdc.gov/nchs/data/nhanes/ba.pdf