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Gait & Posture
journal homepage: www.elsevier.com/locate/gaitpost
Validity and reliability of the Nintendo Wii Balance Board for assessment of standing balance Ross A. Clark a,*, Adam L. Bryant a, Yonghao Pua b, Paul McCrory a, Kim Bennell a, Michael Hunt a a b
Centre for Health, Exercise and Sports Medicine, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Carlton, Victoria 3010, Australia Department of Physiotherapy, Singapore General Hospital, Singapore
A R T I C L E I N F O
A B S T R A C T
Article history: Received 9 July 2009 Received in revised form 10 November 2009 Accepted 15 November 2009 Keywords: Balance Motor control Movement disorder Rehabilitation Force plate Biomechanics Gait Posture
Impaired standing balance has a detrimental effect on a person’s functional ability and increases their risk of falling. There is currently no validated system which can precisely quantify center of pressure (COP), an important component of standing balance, while being inexpensive, portable and widely available. The Wii Balance Board (WBB) ﬁts these criteria, and we examined its validity in comparison with the ‘gold standard’—a laboratory-grade force platform (FP). Thirty subjects without lower limb pathology performed a combination of single and double leg standing balance tests with eyes open or closed on two separate occasions. Data from the WBB were acquired using a laptop computer. The test– retest reliability for COP path length for each of the testing devices, including a comparison of the WBB and FP data, was examined using intraclass correlation coefﬁcients (ICC), Bland–Altman plots (BAP) and minimum detectable change (MDC). Both devices exhibited good to excellent COP path length test– retest reliability within-device (ICC = 0.66–0.94) and between-device (ICC = 0.77–0.89) on all testing protocols. Examination of the BAP revealed no relationship between the difference and the mean in any test, however the MDC values for the WBB did exceed those of the FP in three of the four tests. These ﬁndings suggest that the WBB is a valid tool for assessing standing balance. Given that the WBB is portable, widely available and a fraction of the cost of a FP, it could provide the average clinician with a standing balance assessment tool suitable for the clinical setting. ß 2009 Elsevier B.V. All rights reserved.
1. Introduction Impaired standing balance associated with many health conditions manifests itself in reduced functional ability . Assessment of standing balance has been shown to provide important information in a variety of situations, ranging from prediction of falls in the elderly  through to examining technique during surgery . Consequently, a number of assessment protocols have been devised [3,22]. Laboratory-based assessment using measures of center of pressure (COP) recorded from a force platform (FP) – considered the gold standard measure of balance  – have identiﬁed important outcome measures which are too subtle to detect using a subjective scale . Using a FP to assess standing balance provides useful information, however they are often expensive, difﬁcult to setup and cumbersome to transport and therefore this form of balance assessment is often not feasible in a clinical setting. Consequently, subjective assessment tools which do not require specialized equipment, such as the Berg Balance Scale, are commonly used and have also
* Corresponding author. Tel.: +61 4 3173 7609; fax: +61 3 8344 4188. E-mail address: firstname.lastname@example.org (R.A. Clark). 0966-6362/$ – see front matter ß 2009 Elsevier B.V. All rights reserved. doi:10.1016/j.gaitpost.2009.11.012
been shown to provide valuable information [3,5]. While these protocols are more clinically applicable, they suffer from limitations including ceiling effects and a limited precision to detect small changes...