Psychometric Properties of Instrumented Postural Sway Measures Recorded in Community Settings in Independent Living Older Adults

Abstract

Background: In the last few decades, research related to balance in older adults has been conducted in lab-based settings. The lack of portability and high cost that is associated with the current gold standard methods to quantify body balance, limits their application to community settings such as independent living facilities. The purpose of the study was to examine the test-retest reliability and the convergent validity of static standing balance performance using an accelerometer device. Methods: A total of 131 subjects (85% female, mean age 80 ± 8 years) were included for the validity aim, and a sample of 38 subjects were enrolled in the reliability testing (89% female, mean age 76 ± 7 years). Acceleration data in the anterior-posterior and medial-lateral directions was collected for different standing balance conditions. Test-retest reliability was assessed over two testing visits occurring one week apart. Spearman’s rank correlation coefficient was used to test convergent validity at baseline. Results: Balance measurements showed good to excellent reliability in most of measured parameters and were correlated with mobility measurements. Conclusions: Using a portable accelerometer to quantify static standing postural control provides reliable measurements in community settings.

The Postural Stability Measures Most Related to Aging, Physical Performance, and Cognitive Function in Healthy Adults

“…The negative relationship between the postural sway in the ML direction and the ABC scale indicates that participants with more sway had less confidence in their ability to maintain their balance while performing several daily activities. Several studies also found similar results despite using various measures to quantify subjects' confidence in their balance when compared to the amount of postural sway [42,47].…”

“…Moreover, a recent study found that lateral postural sway measures were more closely related to participants' perceptual assessment of exercise difficulty compared to sagittal postural sway measures [6]. Several studies also indicated that the magnitude of postural sway in the ML direction has more reliability [7,[37][38][39][40][41][42] and was correlated with more physical [42] and self-reported measures [6] as well as number of future falls [34][35][36] compared to that in the AP direction. Several studies provided an explanation for that, where they indicated that the lateral sway has more variation due to the narrow support base while performing balance exercises compared to the sagittal sway, which may allow for greater reliability and more relationships with different measures [6,7].…”