title: Intra-session test-retest reliability of magnitude and structure of center of pressure from the Nintendo Wii Balance Board™ for a visually impaired and normally sighted population.
abstract: Individuals with visual impairment (VI) have irreparable damage to one of the input streams contributing to postural stability. Here, we evaluated the intra-session test-retest reliability of the Wii Balance Board (WBB) for measuring Center of Pressure (COP) magnitude and structure, i.e. approximate entropy (ApEn) in fourteen legally blind participants and 21 participants with corrected-to-normal vision. Participants completed a validated balance protocol which included four sensory conditions: double-leg standing on a firm surface with eyes open (EO-firm); a firm surface with eyes closed (EC-firm); a foam surface with EO (EO-foam); and a foam surface with EC (EC-foam). Participants performed the full balance protocol twice during the session, separated by a period of 15min, to determine the intraclass correlation coefficient (ICC). Absolute reliability was determined by the standard error of measurement (SEM). The minimal difference (MD) was estimated to determine clinical significance for future studies. COP measures were derived from data sent by the WBB to a laptop via Bluetooth. COP scores increased with the difficulty of sensory condition indicating WBB sensitivity (all p<0.01). ICCs in the VI group ranged from 0.73 to 0.95, indicating high to very high correlations, and the normal group showed moderate to very high ICCs (0.62-0.94). The SEM was comparable between groups regardless of between-subject variability. The reliability of the WBB makes it practical to screen for balance impairment among VI persons.
authors.affiliation: Wilmer Eye Institute, Johns Hopkins University, 600 N. Wolfe St., Woods 355, Baltimore, MD 21287, USA. Electronic address: pamela.jeter@gmail.com.
authors.forename: Pamela E
authors.initials: PE
authors.lastname: Jeter
authors.affiliation: Wilmer Eye Institute, Johns Hopkins University, 600 N. Wolfe St., Woods 355, Baltimore, MD 21287, USA. Electronic address: jwang@jhsph.edu.
authors.forename: Jiangxia
authors.initials: J
authors.lastname: Wang
authors.affiliation: Wilmer Eye Institute, Johns Hopkins University, 600 N. Wolfe St., Woods 355, Baltimore, MD 21287, USA. Electronic address: jialiang.gu1@gmail.com.
authors.forename: Jialiang
authors.initials: J
authors.lastname: Gu
authors.affiliation: Wilmer Eye Institute, Johns Hopkins University, 600 N. Wolfe St., Woods 355, Baltimore, MD 21287, USA. Electronic address: mbarry11@jhu.edu.
authors.forename: Michael P
authors.initials: MP
authors.lastname: Barry
authors.affiliation: Wilmer Eye Institute, Johns Hopkins University, 600 N. Wolfe St., Woods 355, Baltimore, MD 21287, USA. Electronic address: crystalroach22@gmail.com.
authors.forename: Crystal
authors.initials: C
authors.lastname: Roach
authors.affiliation: Wilmer Eye Institute, Johns Hopkins University, 600 N. Wolfe St., Woods 355, Baltimore, MD 21287, USA. Electronic address: m.f.corson@gmail.com.
authors.forename: Marilyn
authors.initials: M
authors.lastname: Corson
authors.affiliation: Wilmer Eye Institute, Johns Hopkins University, 600 N. Wolfe St., Woods 355, Baltimore, MD 21287, USA. Electronic address: lindsey@lions.med.jhu.edu.
authors.forename: Lindsay
authors.initials: L
authors.lastname: Yang
authors.affiliation: Wilmer Eye Institute, Johns Hopkins University, 600 N. Wolfe St., Woods 355, Baltimore, MD 21287, USA. Electronic address: gislin@lions.med.jhu.edu.
authors.forename: Gislin
authors.initials: G
authors.lastname: Dagnelie
mesh_terms: D000058:Accidental Falls / Q000517:prevention & control; D000328:Adult; D000704:Analysis of Variance; D001766:Blindness / Q000150:complications* / Q000503:physiopathology / Q000534:rehabilitation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D004856:Postural Balance / Q000502:physiology*; D011312:Pressure; D015203:Reproducibility of Results; D012678:Sensation Disorders / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology* / Q000534:rehabilitation*; D014584:User-Computer Interface; D018910:Video Games
keywords: Approximate entropy; Center of pressure; Reliability; Vision impairment; Wii Balance Board