Psychometric Properties of the Pediatric Balance Scale Using Rasch Analysis

Purpose: The Pediatric Balance Scale (PBS) is a 14-item measure of functional balance for children. This study examined PBS dimensionality, rating scale function, and hierarchical properties using Rasch analysis. Methods: The PBS data were analyzed retrospectively for 823 children, aged 2 to 13 years, with uni- and multidimensional Rasch partial credit models. Results: The PBS best fits a unidimensional model based on the Bayesian information criterion analysis (12 400.73 vs 12 404.48), strong correlations between 3 proposed dimensions (r = 0.946-0.979), and high internal consistency (Cronbach alpha = 0.94). Analysis of rating scale functioning is limited by small numbers of children achieving low scores on easy items. Item maps indicated a ceiling effect but no substantive gaps between item difficulty estimates. Conclusion: The PBS items are best targeted to preschool-age children; additional children with known balance dysfunction are required to fully assess functioning of the easiest PBS items. Revisions may improve PBS utility in older children.