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.