Elsevier

Gait & Posture

Volume 31, Issue 3, March 2010, Pages 307-310
Gait & Posture

Validity and reliability of the Nintendo Wii Balance Board for assessment of standing balance

https://doi.org/10.1016/j.gaitpost.2009.11.012Get rights and content

Abstract

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.

Introduction

Impaired standing balance associated with many health conditions manifests itself in reduced functional ability [22]. Assessment of standing balance has been shown to provide important information in a variety of situations, ranging from prediction of falls in the elderly [14] through to examining technique during surgery [19]. 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 [12] – have identified important outcome measures which are too subtle to detect using a subjective scale [16]. 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 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 in performance [5], [11]. In addition, previous research indicates that the relationship between scores on subjective tests and measures of COP displacement is only moderate [10], and that a combination of the two protocols may provide important information which cannot be obtained by either subjective or quantitative assessment alone [1], [5].

This highlights the need to create a portable, inexpensive balance assessment system that has widespread availability. The Wii Balance Board (WBB) (Nintendo, Kyoto, Japan), part of the popular video game WiiFit, satisfies all of these criteria. The WBB possesses similar characteristics to a laboratory-grade FP in that it contains four transducers which are used to assess force distribution and the resultant movements in COP. Originally designed as a video game controller, the WBB is predominantly used in combination with a video game console and its associated software. Given the capacity for providing instant feedback and the potential for enhanced motivation levels [17], this system has already been integrated into the rehabilitation programs of neurological patients with balance defects [6]. In addition to its use as a biofeedback and gaming tool, the WBB could potentially be used by clinicians to collect and analyse laboratory-grade balance data using the techniques and outcome measures most specific to the patient population of interest. The WBB is a small fraction of the cost of a laboratory-grade FP, is mass-marketed and is portable, and consequently it has the potential to become a key component of a clinician's testing battery if it can be shown to produce reliable and valid results. Therefore, the aim of our study was to compare COP data collected on a WBB with that of a laboratory-grade FP during a variety of balance tests.

Section snippets

Participants

Thirty young (age = 23.7 ± 5.6 years), injury free individuals (gender = 10 male, 20 female; height = 1.68 ± 0.09 m; body mass = 63.80 ± 15.20 kg) were tested on two occasions, completed within 2 weeks and at least 24 h apart. No participant reported a major back or lower limb pathology, use of medication, or a history of neurologic disease that may influence standing balance. The study was approved by the institution's Human Research Ethics Committee and all participants provided informed consent.

Procedures

On each of

Results

The results for the (1) single limb with eyes open, (2) single limb with eyes closed, (3) double limb with eyes open and feet apart and (4) double limb with eyes closed and feet together tests are provided in Table 1. Two participants were unable to successfully complete three trials of single limb balance with eyes closed on Day 1, and therefore did not undergo testing for this task on Day 2. Consequently, test–retest statistical analysis was performed on the data for 30 participants in all

Discussion

The ability for a clinician to objectively assess standing balance using a portable, inexpensive and valid system could provide numerous benefits in a wide range of patient populations. In this respect, we have shown that the WBB exhibits excellent test–retest reliability for COP path length assessment and possesses concurrent validity with a laboratory-grade FP. This provides the impetus for further research into the clinical applications of this video game equipment and the creation of

Source of funding

No external funding was received specifically for this project. No support was received from Nintendo. The first author's research fellow position is funded by ASICS Oceania.

Conflict of interest

There is no conflict of interest.

References (22)

  • J. Fleiss

    The Design and Analysis of Clinical Experiments

    (1986)
  • Cited by (770)

    View all citing articles on Scopus
    View full text