Balance Error Scoring System in the assessment of chronic ankle stability: A systematic review and meta-analysis

Chronic ankle instability (CAI) is a common musculoskeletal injury associated with static balance deficits. The Balance Error Scoring System (BESS) is commonly used to assess static balance in individuals with CAI. However, the sensitivity of BESS in detecting balance deficits in CAI is unknown. This study compared BESS performance between people with CAI and controls and investigated which stances most effectively identified balance deficits in individuals with CAI. Seven electronic databases (Web of Science, CINAHL, Embase, PubMed, Scopus, SPORTDiscus, and Cochrane Library) were searched from July 13, 2023, to September 10, 2023, using the ankle instability and balance related terms as keywords to search original studies and perform a systematic review. Studies that compared BESS scores between individuals with CAI and healthy controls were systematically identified. Extracted data included study characteristics, participant demographics, and assessment details. The risk of bias was assessed using the Newcastle-Ottawa Scale. The standardized mean difference (SMD) and 95% confidence interval (CI) were used as effect sizes to compare groups for the BESS components used to assess CAI. Six studies met the eligibility criteria. The double-leg foam stance yielded an SMD of -0.02 (95% CI: -0.32 to 0.29), with an I value of 3.5%. Significant differences between groups were noted in the single foam (SMD = 0.89; 95% CI: 0.33-1.45; I = 78.3%) and single firm (SMD = 0.62; 95% CI: 0.14-1.10; I = 72.1%) performances, although both demonstrated high heterogeneity. Conversely, the tandem foam (SMD = 0.77; 95% CI: 0.51-1.02; I = 0.0%) and tandem firm (SMD = 0.38; 95% CI: 0.11-0.68; I = 23.8%) performances showed small to moderate between-group differences with considerably lower heterogeneity. This review indicates that tandem stances on foam and firm surfaces in the BESS are reliable indicators of static balance deficits in individuals with CAI.