Assessing Balance Function in Patients With Total Knee Arthroplasty

BACKGROUND: The Balance Evaluation Systems Test (BESTest) is a relatively new balance assessment tool. Recently, the Mini-BESTest and the Brief-BESTest, which are shortened versions of the BESTest, were developed. OBJECTIVE: The purpose of this study was to estimate interrater and intrarater-interoccasion reliability, internal consistency, concurrent and convergent validity, and floor and ceiling effects of the 3 BESTests and other related measures, namely, the Berg Balance Scale (BBS), Functional Gait Assessment (FGA), and Activities-specific Balance Confidence (ABC) Scale, among patients with total knee arthroplasty (TKA). DESIGN: This was an observational measurement study. METHODS: To establish interrater reliability, the 3 BESTests were administered by 3 independent raters to 25 participants with TKA. Intrarater-interoccasion reliability was evaluated in 46 participants with TKA (including the 25 individuals who participated in the interrater reliability experiments) by repeating the 3 BESTests, BBS, and FGA within 1 week by the same rater. Internal consistency of each test also was assessed with Cronbach alpha. Validity was assessed in another 46 patients with TKA by correlating the 3 BESTests with BBS, FGA, and ABC. The floor and ceiling effects also were examined. RESULTS: The 3 BESTests demonstrated excellent interrater reliability (intraclass correlation coefficient [ICC] [2,1]=.96-.99), intrarater-interoccasion reliability (ICC [2,1]=.92-.96), and internal consistency (Cronbach alpha=.96-.98). These values were comparable to those for the BBS and FGA. The 3 BESTests also showed moderate-to-strong correlations with the BBS, FGA, and ABC (r=.35-.81), thus demonstrating good concurrent and convergent validity. No significant floor and ceiling effects were observed, except for the BBS. LIMITATIONS: The results are generalizable only to patients with TKA due to end-stage knee osteoarthritis. CONCLUSIONS: The 3 BESTests have good reliability and validity for evaluating balance in people with TKA. The Brief-BESTest is the least time-consuming and may be more useful clinically.