Assessment of Internal Consistency and Convergent Validity of the Activities-specific Balance Confidence (ABC) Scale Thai Version

Abstract

Objective: To assess the internal consistency of the Activities-specific Balance Confidence (ABC) Scale Thai version and convergent validity of the scale compared with the Fall Efficacy Scale (FES) Thai version and Timed Up and Go Test (TUG). Method:The internal consistency, convergent validity and floor/ceiling effectsof the ABC scale were assessed in 40 healthy older Thai adultswith the mean age of 66.55.7 years. The internal consistency was determined using the Cronbach’s alpha coefficient, item total correlation and Cronbach’s alpha coefficient if itemsdeleted. The convergent validity ofthe ABC scale Thai versionwas assessed using the FES scale Thai version and TUG. Correlations between the scales were determined bythe Spearman’srank correlation, whereas the floor/ceiling effectswereconfirmed bythe skewness analysis. Results:The internal consistency of total ABC scores washigh(Cronbach’s alpha coefficient =0.96). There was a significant correlation between the ABC scale Thai version and theTUG, albeit low degree of correlation (Spearman’s rho = -0.34), and another significant correlation with theFES scale Thai version (Spearman’s rho = 0.66) was identified. There was no significant floor effect in the ABC scale Thai version and the FES scale Thai version, but the ceiling effect was found only in the FES scale Thai version(-1.27). The proportion of those persons with full scoresof the ABC scale was significantlylower than those of FES scale (7.50% vs. 42.50%, P<0.05). Conclusion: the ABC scale Thai version hadthe high level of internal consistency reliability and moderate level of convergent validity with the FES scale Thai version. As the scalehad noceiling or floor effect, it is more sensitive than the FES scale when using in the highlyfunctional older Thai persons.