Validity, Reliability, Inter- and Intra-Class Correlations, and Characteristics of Norms of a New Balance Test

Background: There are many balance tests, but all have significant disadvantages, including ceiling effects, long administration, or limited to people with mild-to-moderate balance disorders. In addition, a balance test that can specifically examine the visual, vestibular and somatosensory systems in standing position is lacking.

Objective: 1) To assess the reliability of the Zur Balance Scale (ZBS) and to determine normal range scores for different age groups, and 2) To differentiate healthy vs. retrospective vestibular subjects (positive vHIT with low VOR gain) using the modified ZBS on the AMTI force plate.

Methods: In this cross-sectional, double-blind study, 88 subjects, ages 29-70 years old, recruited from a high-tech company in Petah-Tikva, were evaluated using the ZBS compared to the Modified Clinical Test Sensory Integration for Balance (mCTSIB). Inter-tester and intra-tester reliability were evaluated, and normal age results were checked. As well we added an additional 27 subjects with a diagnosis of vestibulopathy were compared to 44 of 88 healthy subjects to characterize four common kinematics parameters: Velocity Avg, ML sway, AP sway and Area95.

Results: ZBS had high inter-tester reliability (0.945 Cronbach Alpha, and 0.945 ICC), and high intra-tester reliability (0.938 Cronbach's Alpha). ZBS scores decreased with increasing age. T-tests for all four kinematic parameters were significant (p<0.05) in both mCTSIB and mZBS.

Conclusions: ZBS is a sensitive test to detect balance disorders. It is reliable, simple and easy to administer. The kinematic parameters of the mZBS can differentiate vestibular subjects.