Kazuhiro Miyata, Satoshi Hasegawa, Hiroki Iwamoto, Tomohiro Otani, Yoichi Kaizu, Tomoyuki Shinohara, Shigeru Usuda
Department of Physical Therapy, Ibaraki Prefectural University of Health Science, 300-0394 Inashiki-gun, Japan. E-mail: miyatak@ipu.ac.jp
DOI: 10.2340/16501977-2709

Objective: To clarify and compare the structural validity of 3 Balance Evaluation Systems Tests (BESTest, Mini-BESTest, and Brief-BESTest) in older adults with femoral or vertebral fractures.
Design: Cross-sectional study.
Subjects: Ninety-four older adults (age ?65 years) with femoral or vertebral fractures, who could walk without physical assistance.
Methods: Four BESTest models (BESTest, one-factor Mini-BESTest, four-factor Mini-BESTest, and Brief-BESTest) were examined using confirmatory factor analysis, and the models’ goodness-of-fit was assessed. Unidimensionality of the best-fitting model was confirmed by Rasch principal component analysis on the residuals.
Results: Confirmatory factor analysis showed that the four-factor Mini-BESTest model (comparative fit index?=?0. 952; Tucker-Lewis index?=?0. 937; root-mean square error of approximation?=?0. 060; standardized root-mean-square residual?=?0. 062) has a better structure than other models. The principal component analysis of standardized residuals showed that the variance attributable to Rasch factor was good, with eigenvalues Conclusion: The four-factor Mini-BESTest model shows good structural validity in older adults with femoral or vertebral fracture. Evaluating dynamic balance by focusing on 4 components (anticipatory postural adjustments, postural responses, sensory orientation, and stability in gait) may help therapists in making clinical decisions.

The Balance Evaluation Systems Test (BESTest), a clinical balance measure, categorizes balance into 6 factors. The aim of this study was to determine which short versions of the BESTest, Mini-BESTest, and Brief-BESTest, were most appropriate for assessing balance impairments in older adults with femoral or vertebral fracture. Subjects were older adults (age ?65 years), who could walk without physical assistance. The models’ fitting was evaluated for four BESTest models (BESTest, one-factor Mini-BESTest, four-factor Mini-BESTest, and Brief-BESTest). The four-factor Mini-BESTest model was the only model that had a good fit and reflected the balance ability in older adults with femoral or vertebral fracture. We suggest that the using the four-factor Mini-BESTest model and seeing dynamic balance as composed of four factors may help therapists in making clinical decisions.

ON THE STRUCTURAL VALIDITY OF BESTEST, MINI-BESTEST AND BRIEF-BESTEST
Response to letter to the editor from Franco Franchignoni and Andrea Giordano