Validity and reliability of the Brazilian activities-specific balance confidence scale and determinants of balance confidence in community-dwelling older adults

Abstract

ABSTRACT Introduction: The Activities-specific Balance Confidence scale is the most used tool to quantify balance confidence, a psychological factor related to balance impairment among older adults. Objective: To investigate the validity and reliability of the original and short versions of the Brazilian Activities-specific Balance Confidence scales, to determine cutoff points for balance impairments and to identify the determinants of balance confidence of community-dwelling older adults. Methods: The validity of both versions of the scales was verified by correlating its results with postural balance, fear of falling and mobility (n = 105). Both scales were administered with a 30 min (interrater reliability, n = 158) and 1-week intervals (intrarater reliability, n = 105). Receiver operating characteristic curve was used to determine the cutoff points, and linear regression was applied to identify the determinants of balance confidence. Results: The Brazilian versions of the scale correlated to postural balance, fear of falling and mobility (p < .05). Excellent interrater (α = 0.946, 95% CI: 0.902–0.976; α = 0.932, 95% CI: 0.918–0.960) and intrarater reliability (α = 0.946, 95% CI: 0.905–0.960; α = 0.952, 95% CI: 0.921–0.965) were found for the original and short versions. Values of ≤67% (sensitivity: 81%, specificity: 77.4%) and ≤44% (sensitivity: 87.5%, specificity: 82.1%) were observed to identify balance impairments for the original and short versions of the scale. Physical inactivity, fear of falling, imbalance sensation, and number of falls are the main determinants of balance confidence. Conclusion: Both scales are valid and reliable to assess balance confidence. Cutoff points to identify balance impairments were determined and some factors may act as possible predictors of balance confidence.