Normative data and predictors of postural sway using static and dynamic balance tests in adults aged 20-69 years

Postural sway is subtle adjusting movements when standing that maintain the center of mass within the base of support. Assessing postural sway enables detection of subtle balance impairments, thereby enhancing the sensitivity of balance assessments. Normative data on postural stability for interpretating clinical findings remains insufficient. This study aims to provide a normative dataset and identify predictors of postural sway to serve as a benchmark in clinical settings and research.

One hundred thirty-nine healthy adults (54% women) aged 20-69 years performed static and dynamic balance tests on the Biodex Biosway balance platform (Biosway Portable Balance System 950-460, Biodex Medical Systems, NY). The static balance tests were the Postural Stability Test and the modified Clinical Test of Sensory Integration and Balance (mCTSIB). The dynamic balance tests were the Limits of Stability tests (LOS).

This study provides the first normative dataset for healthy adults aged 20-69 years, stratified by age and sex for static and dynamic balance tests for the Biodex Biosway balance platform. For the mCTSIB, each unit increase in BMI predicted an increase of 0.016 in score (p = 0.015), and each additional year of age predicted an increase of 0.055 in score (p = 0.0007), meaning poorer balance. For the LOS easy level, each unit increase in BMI predicted a reduction of 0.777 in the LOS overall score (p = 0.0297), and each additional year of age predicted a reduction of 0.274 in the LOS overall score (p = 0.0004), meaning poorer balance.

These findings offer clinicians valuable reference values for interpreting individuals' objective balance performance using the Biodex Biosway balance platform. Increased BMI and age were consistent predictors of poorer balance.