Comparison of the Wii Balance Board System and Foam Posturography System in Assessing Postural Balance.

OBJECTIVE: Falls are a major cause of disability and mortality in the elderly. Postural balance is associated with falls and can be evaluated by posturography. However, conventional posturography is costly and requires a sufficiently large space to perform. Hence, this study developed a portable system to meet the requirement of field studies, and investigated its reliability and validity. DESIGN: A custom-written software application was developed to link a computer to the Nintendo Wii balance board (WBB) and the center of pressure was acquired, which was then compared with that obtained from commercially available foam posturography (FP). Forty younger adults including 20 patients with peripheral vestibular disorders as well as 20 healthy controls, and 50 older patients with peripheral vestibular disorders were enrolled. All subjects underwent postural balance testing using the WBB system (WBSS) and FP system (FPS) in a randomized order. RESULTS: For the intersystem reliability, although the WBSS obtained a significantly smaller mean sway area than the FPS, both systems revealed adequate to excellent reliability with an intraclass correlation coefficient (ICC) of 0.67 to 0.87. The WBBS showed adequate to excellent test-retest reliability (ICC: 0.53 to 0.88). For the validity, the respective cutoff sway areas were 1.03 and 3.09 cm 2 under conditions C and D via the WBBS for discriminating the fallers from nonfallers. CONCLUSION: The WBBS yielded adequate to excellent reliability and validity for accessing postural balance, and had good performance in discriminating the fallers from nonfallers. The WBBS has advantages over the commercial FPS of low cost, easy portability, programmability, and may be better-suited to mass detection and research programs. Most importantly, this WBBS can be performed outside the hospital for testing postural balance, especially in the elderly.