Validity and reliability of Nintendo Wii Fit balance scores.
BACKGROUND
Interactive gaming systems have the potential to help rehabilitate patients with musculoskeletal conditions. The Nintendo Wii Balance Board, which is part of the Wii Fit game, could be an effective tool to monitor progress during rehabilitation because the board  and game can provide objective measures of balance. However, the validity and reliability of Wii Fit balance scores remain unknown.


OBJECTIVE
To determine the concurrent validity of balance scores produced by the Wii Fit game and the intrasession and intersession reliability  of Wii Fit balance scores.


METHODS
Descriptive laboratory study.


METHODS
Sports medicine research laboratory.


METHODS
Forty-five recreationally active participants (age = 27.0 ± 9.8 years, height = 170.9 ±  9.2 cm, mass = 72.4 ± 11.8 kg) with a heterogeneous history of lower extremity injury.


METHODS
Participants completed a single-limb-stance task on a force plate and the Star Excursion Balance Test (SEBT) during the first test session. Twelve Wii Fit balance  activities were completed during 2 test sessions separated by 1 week.


METHODS
Postural sway in the anteroposterior (AP) and mediolateral (ML) directions and the AP, ML, and resultant center-of-pressure (COP) excursions were calculated from the single-limb  stance. The normalized reach distance was recorded for the anterior, posteromedial, and posterolateral directions of the SEBT. Wii Fit balance scores that the game software generated also were recorded.


RESULTS
All 96 of the calculated correlation coefficients among Wii Fit  activity outcomes and established balance outcomes were interpreted as poor (r < 0.50). Intrasession reliability for Wii Fit balance activity scores ranged from good (intraclass correlation coefficient [ICC] = 0.80) to poor (ICC = 0.39), with 8 activities having poor intrasession  reliability. Similarly, 11 of the 12 Wii Fit balance activity scores demonstrated poor intersession reliability, with scores ranging from fair (ICC = 0.74) to poor (ICC = 0.29).


CONCLUSIONS
Wii Fit balance activity scores had poor concurrent validity relative to COP outcomes  and SEBT reach distances. In addition, the included Wii Fit balance activity scores generally had poor intrasession and intersession reliability.
Department of Kinesiology and the Center for Biomedical Engineering Science, University of North Carolina at Charlotte, 9201 University City Boulevard, Charlotte, NC 28223, USA. ewikstrom@uncc.edu
Erik A
EA
Wikstrom
D000293:Adolescent; D000328:Adult; D015444:Exercise; D006801:Humans; D007869:Leg Injuries / Q000534:rehabilitation; D008875:Middle Aged; D004856:Postural Balance; D015203:Reproducibility of Results; D018910:Video Games; D055815:Young Adult